Group IIA - SSCC 1713 (20212022-2) 80 by SHEELA CHANDREN

Summary Carbonate compounds of Group IIA

maizurahnazri01 — 2022-04-18 17:52:39 UTC

NURMAIZURAH BINTI NAZRI (A21HP0167)

To prepare the carbonate of group IIA such as we used encountered like CaCO3 or known as limestone, we need to react CaCl2 with sodium carbonate to yield limestone, CaCO3 and get sodium chloride as side product. But, group IIA not only calcium we can use, Magnesium also popularily can be as magnesite, MgCO3 also but to get this one, we should not use sodium carbonate, NaCO3 as it is too basic and let to yield basic magnesium carbonate which is not the one magnesite we need to yield. So, to yield the magnesite, MgCO3 we have to use sodium hydrogen carbonate no matter what and react it with magnesium nitrate, Mg(NO3)2 so we could get the MgCO3 which is the carbonate of group IIA.

Next, for the properties for the carbonate include with solubility and thermal stability and reaction with mineral acids. Firstly, for solubility, we need to remember the part when go down the group. solubility will decreases. When it comes to solubility, these two terms need to remember well which are lattice energy and hydration energy. These two have the relation with the size of ion. For example, if the size of ion bigger, so the hydration energy becomes less negative(-ve) and lattice energy becomes less positive(+ve) due to the decrease in polarizability of ions or lower the charge density and vice versa. To be easier to remember, if hydration energy less negative, it means difficult to soluble and if lattice energy less positive, it means easier to soluble.

Secondly, thermal stability will increases when it down the group due to the decrease in polarizability. As I was talked before about the solubility but this one is about decomposition compound. When the positive ions becomes bigger when it down the group, the compounds will have less effect on the carbonate ion, it means decreases in polarizability, so they need to heat more the compound to make sure they get to break off the carbon dioxide and lastly get to give the metal oxide. The tendency to decompose the compound will decreases when it start to go down the group as I said like the above when go down the group, the size of ions get more bigger, the less effect on carbonate ion lead to the lower the charge density. That is why to decompose those ions, we have to heat more. Therefore, lagi senang decompose, thermal stability berkurang.

Furthermore, the keyword for thermal decomposition and play important parts are charge density and polarizing power of cation. For example, when the charge density of the cation decreases, so same goes with the polarizing power of cation will become weaker. Consequently, it make cation has polarizing power but less able to polarize the anion and lead to less able to distort or weakens covalent bond that was found in carbonate ion.

Next, stability of the oxyanion will increases when down the group due to the strength of ionic bonding among cation & anion decreases lead to the bond strength between atoms in oxyanion increases. Beside that, due to the decomposition occur if the strength between anion and cation increases. Maksudnya, semakin kuat ikatan tersebut, semakin senang terputus.

For polarizing carbonate ion that I have mentioned above, it means the positive ions get to attracts with the delocalized electrons in the carbonate ion toward itself. The delocalized electrons happens when the greater electron density around the oxygen atoms than the carbon.

Question: Dr, the polarizing means when the cation attract to delocalized electrons right. But can I understand by telling or is it right the polarizing term always use in explanation when the decomposition compound need to occur only?

Oxide compound in Group iiA

2022-04-19 04:20:31 UTC

Muhd Sabri..

Preparation for oxide compound (MO)
have to method which are in industry and in laboratory. For in industry, to produce oxide compound of Group iiA is by heating carbonate salts of Group iiA metals and it's will produce oxide and co2 as the side product. For laboratory, we also heat buat we can use three type of metal like below:
MCO3 heat produce MO and CO2
M(OH)2 heat produce MO and H20
M(NO3)2 heat produce MO + 4NO2 + 02

Type bond of metal oxides are ionic expect for BeO. Trend of solubity of metal oxide is increasing from BeO,MgO,,SrO and BaO. When heated in pure oxygen, the elements like Be,Mg,Ca and Sr will form monoxide while Ba formed peroxide(BaO2) under pressure. The formation is due to the divalent metal ions are sufficiently polarising.

The melting point of monoxide decrease down the group.
MgO>CaO>SrO>BaO
It's due to increasing cation size from Mg to BA which slightly reduced in lattice energy.

Semua oxide adalah base except for BeO it's amphoteric. Utk tgk basicity kna tgk pada msa reaction oxide dgn water. Jika lagi bnyk oxide tersebut release more OH ia akan jadi lebih basic. Ia juga dilihat pada greater the difference in electronegativity of elements, makin ionic metal-oxygen bond and ia akan jadi lebih ionic characteristics. Lastly it will be more basic.
Thank you✨

Summary of hydroxide compund in Group IIA

2022-04-19 07:19:09 UTC

Ain Asreena Binti Ramli
The molecular formula for elements in group IIA is M(OH)2, where M=Be,Mg,Ca,Sr,Ba and Ra. These compound exists as white solid and are ionic compound except Be(OH)2.
Solubility:
(Be(OH)2As we go down the group, the solubility increases, due to the decreasing of lattice energy. But, due to the difference in size and lattice energy, Be(OH)2 is insoluble in water. Be(OH)2 has very small cation size,thus the interaction between nucleus and valence electron become stronger,so more energy required to separate a mole of an ionic solid into gaseous ions.Therefore, Be(OH)2 has higher lattice energy cause it insoluble.
Thermal stability: (Be(OH)2As we go down the group, thermal stability increase. This is because, as the size of compound increases, ionization energy of the element decreases. So, it is easy for one element to give electrons to another which can cause lattice energy to increase. And lattice enthalpy value is directly proportional to the thermal stability of hydroxide.
Basicity:
( Be(OH)As we go down the group, the basicity increases. This is because the ionization energies of these metals are low, where the M-O bond in MOH is weak and it can cleave to give OH^- ions in solution. Therefore, there will be a greater concentration of OH- ions in water. So, when the ionization energy decreases down the group, the basic strength of the hydroxides increases. Be(OH)2 is amphoteric, they can react to acids and strong bases like NaOH.

Chloride (MCl2)

2022-04-19 17:27:03 UTC

Metal Clorides (M can be either Mg, Be, Ca, Ba and etc)

1. Preparation of Maganese Chloride (Example)

- MgO + C + Cl2 -> MgCl2 + CO
- MgO + 2HCl -> MgCl2 + H

2. Properties
- All metal chlorides are ions in nature except for BeCl2 which is covalent.
- In nature, Be it can only be found in compounds with other elements.
- Anhydrous MCl2 salt is obtain heating the dehydrated chloride salts (except MgCl2.6H2O)

MCl2.mH2O - H2O ---> MCl2 anhydrous
heat
if M=Mg
MgCl2.6H2O ---> Mg(OH)Cl + HCl + 5H2O
heat (hydroxychloride)

Anhydrous magnesium chloride cannot be dehydrated by heating.

MgCl2.6H2O + HCl(g) ---> MgCl2
(anhydrous)

Anhydrous magnesium chloride can be produced by the dehydration of magnesium chloride hydrate in HCl gas atmosphere, and found that anhydrous magnesium chloride can be prepared from ammonium magnesium chloride hexahydrate at the reaction temperature range 50–400°C and a reaction time of 30min even in air atmosphere.

3. Application

- MgCl2

Magnesium chloride is used for low-temperature de-icing of highways, sidewalks, and parking lots. When highways are treacherous due to icy conditions, magnesium chloride helps to prevent the ice bond to the pavement, allowing snow plows to clear the roads more efficiently.

- CaCl2 (anhydrous)
It has several common applications such as brine for refrigeration plants, ice and dust control on roads, and in concrete. The anhydrous salt is also widely used as a desiccant, where it will absorb so much water that it will eventually dissolve in its own crystal lattice water (water of hydration).

SUMMARY COMPOUND OF GROUP IIA : HYDRIDE

2022-04-19 18:48:29 UTC

NUR SUHAILA BINTI SHUKOR ( A21HP0151 )

Hydride has molecular formula which is MH2. to prepare the hydride, for all the elements of group IIA ; Mg, Ca, Sr and Ba can undergo direct heating with hydrogen gas. But except for Be that cannot straight away heating with H2. Be in the form of BeCl2 react with LiAlH4 and ether to form hydride with some side product.

2BeCl2 + LiAlH4 -> BeH2 + LiCl + AlCl3

While the properties of hydride are all hydride are ionic which means they contain H-, plus with M+.
However, exception for BeH2. BeH2 is a covalent compound because it can form polymeric solid which means Be atom linked by hydrogen bridging. Due to that, it can complete the octet of Be.

Besides, hydride can undergo reaction with water to form hydroxide and hydrogen gas.
but only for element from Mg to Ba.

e.g : MgH2 + 2H2O ->Mg(OH)2 + H2(g)

While in terms of thermal stability , go down the group starting from Mg to Ba, the thermal stability increasing due to the polarizability. so, more higher temperature needed to decompose it.

SUMMARY COMPOUND OF GROUP IIA : SULPHATE

2022-04-20 04:32:15 UTC

MIZA FAIQAH BINTI SUHAIMI (A21HP0059)

Metal sulphate has molecular formula MSO4. In order to prepare metal sulphate of group IIA, they have to react their metal salt with sulphuric acid. Different types of element have different of metal salt. For example :

MX + H2SO4 ----> MSO4 +HX

M = BE X = O

M = Mg X = CO3

M = Ca, Sr, Ba X = Cl

Properties of metal sulphate are all sulphate salt exist in hydrated form or known as hydrated salt. Hydrated salt is a crystalline salt molecule that is loosely attached to a certain number of water molecules. This is only physical attraction that easy to break. The number of mole hydrated water depends on the temperature. For example :

MgSO4 with 7H2O known as Epsom salt

CaSO4 with 2H2O known as Gypsum salt

CaSO4 with ½ H2O known as Plaster of Paris

Second properties is thermal stability of group IIA in sulphate increase down the group. It will decomposed to oxide when heated. Reason of the increasing of thermal stability when go down the group is due to the deacrease in polarizing ability of cation. Its hard to disrupt the bonding inside sulphate. Hence, need more energy to break down the bond.

BeSO4 < MgSO4 < CaSO4 < SrSO4 < BaSO4

Next, solubility decrease down the group

BeSO4 > MgSO4 > CaSO4 > SrSO4 > BaSO4

The solubility of metal sulphate of group IIA is depends on two things which is lattice energy and hydration energy. In lattice energy, it involve 2 process. First process is separation of ions in lattice to free ions in gas

M2+X2-(p) ---> M2+(g) + X2-(g)

While in second process is hydration of the free ions by water that involve hydration energy. For group IIA, the hydration energy is related with polarize ability. The stronger of polarizing ability, the higher hydration energy which make it easy to interact with water. If lattice energy required (+ve) is higher than hydration energy required (-ve), the total enthalpy of dissolution will be more +ve (endothermic). Hence, the salt does not dissolve. While If lattice energy required (+ve) is lower than hydration energy required (-ve), the total enthalpy of dissolution will be more -ve (exothermic). Hence, salt easily to dissolve.

Application of metal sulphate such as for Epsom Salt (MgSO4), it uses as a medicine (saline laxative), fertilizer, coagulant for making tofu and as a drying agent (anhydrous). For Gypsum salt (CaSO4) , it uses for Portland cement, plaster, chalk, gypsum board and fertilizer in agriculture. Another one is BaSO4 which know as “Barium meal” that use as X-ray in order to obtain good quality of digestive tract.

SUMMARY COMPOUND OF GROUP IIA: SULPHATE

2022-04-20 05:14:30 UTC

MUHAMMAD AFKAR BIN NORALIMIN (A21HP0074)

Preparation:
ada satu saja iaitu reaction of the metal salt with sulpharic acid (H2SO4)
Untuk unsur Beryllium (Be):
BeO + H2SO4 -> BeSO4 + OH
Untuk unsur Magnesium (Mg):
MgCO3 + H2SO4 -> MgSO4 + HCO3
Untuk unsur Calcium (Ca), Strontium (Sr) dan Barium (Ba):
MCl + H2SO4 -> MSO4 + HCl

Properties:
1)semua sulphate salts = hydrated form
hydrated salts = crystalline salt molecule that is loosely attached to a certain number of water molecules.
number mole of hydrated water bergantung kepada suhu
MgSO4.7H2O = Epsom salt
CaSO4.2H2O = Gypsum salt
CaSO4.1/2H2O = Plaster of Paris
2) Thermal stability increase when down the group
BeSO4 < MgSO4 < CaSO4 < SrSO4 < BaSO4
decomposed to oxide when heated
stability increase sebab polarizing decrease. size of M2+ increased down the group cause charge density and polarizing power decreased (size cation besar power untuk nucleus tarik electron valence kurang) bila kurang tarikan anion dan kation, tarikan di dalam anion (sulphur dan 4 oxygen) menjadi lebih kuat. Hence, more stable when heated.
polarizing: The ability of an atom to deform the electron cloud of an atom
3) Solubility decrease when down the group
BeSO4 > MgSO4 > CaSO4 > SrSO4 > BaSO4
solubility decrease because of larger anion compare to M2+. Lattice energy decrease (more +ve). size cation not contribute with size anion (size sama besar susah nak larut) jadi ia akan mengurangkan hydration energy (less -ve).

Application of Metal Sulphate:
Epsom Salt (MgSO4)
1) Medicine (saline laxative)
mineral supplement to control low blood levels of magnesium
Magnesium sulfate injection is also used for pediatric acute nephritis and to prevent seizures in severe pre-eclampsia, eclampsia, or toxemia of pregnancy.
2) Fertilizer (for soil amendment) Mg for chlorophyll
3) coagulant to make tofu
4) anhydrous - drying agent
Gypsum Salt (CaSO4)
1) Portland Cement
2) Plaster of Paris
3) mould, chalk
4) gypsum board
5) fertilizer in agriculture
6) dentistry - used in bone regeneration as a graft material and graft binder
BaSO4
Medicine - used as barium meal to help diagnose or find problems in the esophagus, stomach, and bowels.

Question:
Dr, ada tips ke nak ingat pasal solubility ni hehe. sampai skarang saya jadi pening?

SUMMARY COMPOUND GROUP IIA (HYDRIDE/MH2)

2022-04-20 13:16:57 UTC

AISYAH BINTI NAZERI (A21HP0012)

Hydride or MH2 is one of the compound in Group IIA element. The element consist from Mg … Ba can undergo the hydride process by direct heating but for Be is anomaly that other Group IIA element, Be have to undergo other reaction to provide BeH2

M+ H2 → MH2
M=Mg...Ba
For Be (Ether as catalyst)
2BeCl2 + LiAlH4 → BeH2 +LiAl + AlCl3

All metal hydride are ionic compound and contain H- ion except Be
BeH2 are covalent bonding(Polymeric solid) and link by H2 bridge

Reaction
1. with water
MH2 + 2H2O → M(OH)2 + 2H2 (M=Mg...Ba)

2. Thermal Stabilization
MH2→M+H2
(Mg→→→→→→→→
(increasing thermal stability)

As we go down the Group IIA thermal stability increase and need more heat to break the bond of anion and cation

SUMMARY COMPOUND OF GROUP IIA (ALKALINE EARTH METALS):SULPHATE

2022-04-20 15:46:11 UTC

Sulphate is one of the compounds in the group IIA (Alkaline earth metal) .Metal sulphate has formula MSO4.

Preparation :

To prepare the metal sulphate, they need to undergo reaction between metal salts with sulphuric acid (H2SO4).

MX + H₂SO₄ → MSO₄ + HX

While M and X can be change according to the metal sulphate that we need:

M=Be X=O

M=Mg X=CO₃

M=Ca,Sr,Ba X=Cl

Properties:

Sulphate comes with a lot of properties.

All sulphate salts exist in hydrated form or (crystal form).The number of mole of hydrated water depends on the temperature used.For example :

MgSO₄.7H₂O : Epsom salt
CaSO₄.2H₂O: Gypsum salt
CaSO₄.¼ H₂O: Plaster of Paris

Thermal stability of sulphate increases down the group due to the decreasing in polarizing ability of cation.The ionic radius get bigger down the group,as the size of the ion increases , the polarizing power decreases,so the compound is more stable and needs more heat to decompose to oxide.

BeSO₄< MgSO₄< CaSO₄44
----------------------------→
INCREASE STABILITY

The solubility of sulphate decreases down the group because hydration energies decrease with increasing cation size.

BeSO4 > MgSO4 >CaSO >SrSO4> BaSO4
-----------------------------→

DECREASE SOLUBILITY

Application:

Epsom salt (MgSO₄) acts as medicine,fertilizer,coagulant for making tofu and act as a drying agent (anhydrous) that always found in the laboratory.
Gypsum salt (CaSO₄) acts as Portland cement,Plaster,mould, fertilizer in agriculture and also chalk.
BaSO₄ acts as an important thing in medicine (Barium Meal).Barium Meal was given to the patient in order to obtain a good quality photograph of the digestive tract because it is opaque to X-rays.

That all from me,Thank you Dr 🌸

Summary Compound of Group IIA: Hydroxide-M(OH)2

2022-04-21 16:36:52 UTC

NUR SYIDAH BINTI SALIM (A21HP0156)

Hydroxide can be prepared by the reaction between metal oxide and water except for Be and Mg.
i) MO + H20--> M(OH)2
ii) For Be, it will be:
BeCl2 + 2NaOH --> Be(OH)2 + 2NaCl
iii) For Mg, it will be:
MgSO4 + 2NaOH --> Mg(OH)2 + Na2SO4
Physiochemical Properties of Hydroxide:
i) Exist as white solid
ii) All are ionic except Be(OH)2
iii) Solubility increases down the group from Be to Ba due to decrease in lattice energy (more -ve). However, Be(OH)2 is insoluble since Be are small cation size, the interaction between nucleus and valence electron increases. Thus, more energy is needed to separate them.
iv) Thermal stability increases down the group due to the decrease in polarizing power of M2+ (hydration energy) down the group and the lower lattice energy of MO product.
v) Basicity increases down the group because:
- solubility increases
- metal ions get larger, so the density increases (means that the cation of Group IIA doesn't hold onto hydroxide ions strongly. More hydroxide ions will release in water. More soluble)
- get lower attraction between hydroxide ions and larger 2+ ions
- The ion will easily split away from each other
- The concentration of hydroxide ions in the water increases.

SUMMARY COMPOUND OF GROUP II : OXIDE (M0)

2022-04-21 19:21:04 UTC

Oxide is one of the six compounds in the group IIA with formula MO.

PREPARATION:

Can be divided into two:

-Industry

-Laboratory

1)Industry: heating carbonate salts of Group IIA metals =

MC03 -> MO + CO2

2)Laboratory =

MCO3 -> MO +CO2

M(OH)2 -> MO + H20

M(NO3)2 -> MO + 4NO2 + 02PROPERTIES:
-All metals oxides are ionic except for BeO
-Can form peroxides but due to the size Be to Sr only can form monoxides.
-But,Ba can formed peroxides (BAO2) under pressure.

-Solubility
*Down the group,the solubility will increase
BeO < MgO < CaO < SrO < BaO
* This is because,if we go down the group,the size will be increase/bigger,so it will less polarize and the interaction with solvent will be less.
*So,the hydration energy and lattice energy will decrease due to increase to the cation size

-Melting Point
*Down the group,the melting point will be decrease,so it will easy to melt
*This is because of the decreasing of cation size and the reduces in lattice energy.

-Basicity
*All oxides are base (except for BeO because it is amphoteric.)
*Down the group the basicity will be increase.
MgO < CaO < SrO < BaO
* This is because when the size of cation increase,it will easier the lose of electron and more electropositive.
* Oxides is very electronegativity,so when go down the group,the electronegativty will be decrease and the different in electronegativity will increase,thefore the oxides will be more basics.

That's all my summary for this compound.Thank you,Dr :)

Summary of Hydroxide Compound in Group IIA- Ong Shi Ting A21HP0181

2022-04-22 01:35:23 UTC

The molecular formula of the hydroxide compound in Group IIA is M(OH)₂, where M = Be, Mg, Ca, Sr, Ba, Ra. All the hydroxide compounds in Group IIA are white solid. Besides, they are ionic compound except Be(OH)₂.

1. Preparation:

a) Be(OH)₂

BeCl₂ + 2 NaOH → Be(OH)₂ + 2 NaCl

b) Mg(OH)₂

MgSO₄ + 2 NaOH → Mg(OH)₂ + Na₂SO₄

c) M(OH)₂, where M = Ca, Sr, Ba
MO + H₂O → M(OH)₂

2. Solubility:

When going down the group, the solubility increases. This is due to lattice energy decreases. But, Be(OH)₂ is completely insoluble because Be²⁺is small cation size. The interaction between nucleus and valence electron increases. Therefore, more energy is required to separate them. The lattice energy will be more positive.

Be(OH)₂ < Mg(OH)₂ < Ca(OH)₂ < Sr(OH)₂< Ba(OH)₂

3. Thermal Stability:

When going down the group, the thermal stability increases.

This is due to:

a) the decrease in polarizing power of M²⁺when going down the group

b) lower lattice energy of MO product

But, Be(OH)₂is unstable because when heating the Be(OH)₂ , it is easily decompose to oxide.

Be(OH)₂→ BeO + H₂O

Be(OH)₂ < Mg(OH)₂ < Ca(OH)₂ < Sr(OH)₂< Ba(OH)₂

4. Basicity

When going down the group, the basicity increases.

This is because:

a) solubility increases
b) metal ions get larger, charge density decreases

c) lower attraction between the OH^- ions and the larger 2⁺ions

d) the ions split away from each other more easily (less lattice energy is needed)

e) More OH^- ions release into the water (greater concentration of OH^- ions in water)

f) Therefore, the basicity increases

** Be(OH)₂ is amphoteric.

Be(OH)₂ < Mg(OH)₂ < Ca(OH)₂ < Sr(OH)₂< Ba(OH)₂

SUMMARY COMPOUND OF GROUP IIA : OXIDE (MO)

2022-04-22 08:18:36 UTC

CHE NURUL ALYA FATNIN BINTI CHE SUHAIMI (A21HP0024)

Oxide with formula MO is one of the compound in group IIA element (Alkaline earth metal).

PREPARATION:-
1. Industry: by heating carbonate salts of Group IIA metals:
MCO3 -> MO + CO2

2. Laboratory: form M= Mg and Ca
MCO3 -> MO + CO2
M(OH)2 -> MO + H20
M(NO3)2 -> MO + 4NO2 + O2

PROPERTIES:-

All metal oxides are ionic (except for BeO)
The divalent metal ions re sufficiently polarizing to make peroxide when heated in pure oxygen. Therefore due to size Be to Sr, it can form only monoxide (MO).
Ba can formed peroxides, BaO2 under pressure.

Solubility

Increases down the group (from Be to Ba)

BeO < MgO < SrO < BaO

Due to size of cation.
When we go down the group, size will increase, so it less polarize and less interaction with solvent.
The hydration energy (weaker interaction with water) and the lattice energy will decrease (weaker bond with the anion) due to the increase in cation size.

Melting point

Decreases down the group
Due to increasing cation size (from Mg to Ba) which slightly reduces in lattice energy.

Basicity

All oxides are base (except for BeO (Amphoteric).
When down the group, basicity will increase.

BeO < MgO < CaO < SrO < BaO

The greater the difference in electronegativity, the more ionic the metal-oxygen bond becomes
More ionic characteristics, more basic.

That's all from me. Thank you Dr🌸

Summary: Compound of Group IIA- Han Shin Ni A21HP0033

2022-04-22 09:08:37 UTC

Carbonate (MCO₃)

Preparation

MgCO₃

Mg(NO₃)₂ + 2NaHCO₃ → MgCO₃ + 2NaNO₃ + H₂O +CO₂

CaCO₃

CaCl₂ + Na₂CO₃ → CaCO₃+ 2NaCl

Solubility (Decreases down the group.)
BeCO₃ > MgCO₃ > SrCO₃ > BaCO₃

Going down the group:

The decrease in lattice energy is small, because the size of anion (CO₃^2-) is larger, so the size of cation does not contribute to affect the lattice energy.
Ionic radius of cation increases.
Polarizability of ions towards water decrease.
Weaker bonding between the ions toward the solvent.
Therefore, less energy will be released.
Hydration energy becomes less negative.

Thermal stability (Increase down the group.)

MCO₃ → MO + CO₂

Going down the group:

Ionic radius increases.
Charge density of cation decreases.
Polarizability decreases.
Give less effect to carbonate ion.
More heat is required to force the carbon dioxide to break off and leave the metal oxide.

Uses of Limestones (CaCO₃)

Fuel industry
Solvay process
Building material
Portiand cement
Antacid
Diet enrichment

SUMMARY COMPOUND OF GROUP IIA (OXIDE)

2022-04-22 11:14:09 UTC

Darshiny Muralitharan

Formula for oxide: MO

Preparation
- Industry: By heating carbonate salts of Group IIA metals;
. MCO3 --> MO + CO2 ( Mg,Ca)

- Laboratory: For M = Mg and Ca
. MCO3--> MO + CO2
. M(OH)2--> MO + H2O
. M(NO3)2--> MO + 4NO2 + O2

Physicochemical Properties

- All metal oxides are ionic ( except BeO)
- The divalent metal ions are sufficiently polarizing to make peroxide when heated in pure oxygen. Therefore
. Be---> Sr ( form only monoxide)
. Ba can form peroxide under pressure

Solubility

- Solubility of oxides increases down the group ( Be---> Ba)
- Because the hydration energy and the the lattice energy decreases due to increase in cation size. ( size incompatibility)
- But the decrease in lattice energy is larger than the decrease in hydration energy resulting in -ve value for the total dissolution energy.
- Hence solubility decrease down the group.

Melting Point
- Melting point of the monoxide decreases down the group due to increase in the size of cation ( Mg-->Ba) which slightly reduces in lattice energy.

Basicity
- All oxides are base ( except BeO is a amphoteric)
- Basicity increases down the group
- The greater the difference in electronegativity the more ionic the metal- oxygen bond becomes
- More ionic characteristics,more basic

SUMMARY COMPOUND OF GROUP IIA ( HYDRIDES & OXIDES) FARIS AIMAN

2022-04-22 19:16:25 UTC

HYDRIDES (MH₂)

Preparation:

1. Untuk mendapatkan Hydrides daripada elemen IIA, boleh dijalankan dengan kaedah Direct Heating bersama H₂ 2_.Kaedah ini tidak boleh terpakai kepada elemen Be. Be perlu berada dalam keadaan BeCl₂dan dipanaskan bersama LiAlH₄.

Be: BeCl2 + LiAlH4 -> 2BeH₂ + LiCl + AlCl₃
M ( Mg -> Ba ): M + H₂ -> MH₂PROPERTIES

- Ionic in nature + contain Hydrogen ion.
- Hanya Be dikategori sebagai Polymeric Solid ( ada Covalent Bond ).

REACTIONS

1. Dengan Air

General Formula:
MH₂+ 2H₂O -> M(OH)₂ + 2H₂
BaH₂ + H₂O -> Ba(OH)₂ + H₂2. THERMAL STABILIZATION

MH₂-> M + H₂
Thermal stabilization increase down the group IIA.

Kedua-dua reaksi tidak melibatkan elemen Be.

OXIDES (MO₂)

PREPARATION

Industry: Heating Carbonate Salts of IIA.
MCO₃ -> MO + CO₂ M= Mg, Ca

Lab: M ( Mg, Ca )
2M(OH)₂ -> 2MO + 2H₂O
2M(NO₃)₂ -> 2MO + 4NO₂ + O₂PHYSICOCHEMICAL PROPERTIES

- Kesemua Metal Oxides adalah ionic kecuali Be.

- Apabila dipanaskan dengan Oxigen, hanya Monoxides( O^2- ) dan Peroxides( 0₂^2- ) sahaja yang boleh dihasilkan.

- Superoxides ( O₂^-) mustahil untuk terhasil.

- Be-> Sr boleh menghasilkan Monoxides
- Hanya Ba yang boleh menghasilkan Peroxides dengan di bawah tekanan.

- Solubility Oxides bertambah menuruni kumpulan IIA.

- Melting Points berkurang menuruni kumpulan Earth Metal Alkaline disebabkan oleh penambahan saiz cation daripada Mg ke Ba. Be tidak termasuk dalam ciri ini.

- Oxides adalah Basic kecuali BeO( Amfoterik).

- Electronegativity berkurang menuruni kumpulan 2, namun Difference Electronegativity bertambah menuruni kumpulan 2.

SUMMARY : COMPOUND OF GROUP IIA (HYDRIDE) - IRENE MICHELLE A21HP0040

2022-04-22 20:04:11 UTC

Hydride (MH2)

Preparation

All the elements in Group IIA ( Mg, Ca, Sr,Ba) can undergo the direct heating with H2. (except for Be)

M(p) + H2(g) --> MH2(p0 ; (M = Mg.....Ba)

Be in the form of BeCl2 can react with LiAlH4 and ether to form BeH2 along with some products.

2BeCl2 + LiAlH4 --> BeH2 + LiCl + AlCl3

Properties

All the metal hydrides are Ionic in nature and contain H- ion and M+ ion.
Except for BeH2, this compound is covalent compound because it is polymeric solid in which Be atom linked by hydrogen bridges.

Reactions

Reaction with H2O

MH2 + 2H2O --> M(OH)2 + 2H2 (M= Mg....Ba)
e.g : MgH2 + 2H2O --> Mg(OH)2 + H2(g)

2. Thermal Stability

In Group IIA , go down the group , thermal stability will increase due to polarizability.

MH2 --> M + H2
Mg < Ca < Sr < Ba

Summary of Trends Group IIA

Thermal Stability : - Increases down the group
BeX< MgX< CaX< SrX< BaX
Basicity : - Increases down the group
BeX< MgX< CaX< SrX< BaX
- Oxides : Change in electronegativity increase, more ionic the bond, more basic the oxide
- Hydroxides : Lower attraction between OH- and larger M2+ cation, easily split away, more OH- ions in H2O.

IMAN ADLINA (SULPHATE)

2022-04-23 01:22:28 UTC

SULPHATE:

· Preparation – undergo direct heating except Be

Metal + H₂SO₄ (MX+H₂SO₄---M₂SO₄ + HX)

· Properties: in hydrated form (.H₂0) --- mole of water depends on temperature.

Ex: Epsom Salt (MgSO_4.7H₂O), Gypsum Salt (CaSO_4.2H₂O)

· Thermal Stability: down the group increase (due to polarizing decrease), need more energy to break the bond sebab saiz M2+ ion increase down the group, decomposed to oxide when heated

BeSO₄< MgSO₄< CaSO₄< BeSrSO₄< BaSO₄

· Solubility: down the group decrease (more +ve)

BeSO₄>MgSO₄> CaSO₄> SrSO₄> BaSO₄

Solubility depends on lattice energy and hydration energy

Decrease due to larger size anion than M2+ ion (tak ngam to each other)

All alkali metal sulphate soluble in water

· Application of metal sulphate:
Epsom salt(MgSO₄): medicine(saline laxative), fertilizer(soil amendment), anhydrous(drying agent),coagulant(making tofu)

Gypsum Salt(CaSo₄): Portland cement, plaster of Paris(hasil crystallysed CaSO₄), mould, chalk, fertilizer in agriculture

BaSO₄: utk legapkan track dekat digestive system, so boleh nampak which part ada clogged/bocor

SUMMARY COMPOUND OF GROUP IIA - LAI LI YIE A21HP0049

2022-04-23 01:28:56 UTC

Carbonate (MCO3)

PREPARATION IN LABORATORY
i.) MgCO3
Mg(NO3)2 + 2NAHCO3 ->MgCO3 +2NaNO3 + H2O +CO2

ii.) CaCO3
CaCl2 +Na2CO3 -> CaCO3 +2NaCl

SOLUBILITY OF MCO3
When going down Group 2,
-size of cation increase,
-the smaller the cation, the higher the charge density and greter effect on carbonate ion
-Since size of cation getting larger, it has less effect on carbonate ions
-The ionic compound becomes more stable
-Decrese of lattice energy is small
-Hydration energy will become less exothermic

THERMAL STABILITY OF MCO3

MCO3->MO + CO2

When going down group 2,

-ionic radius increases
-charge density of cation decreases
-Polarizability of cation decreases
-Cation difficult to distort electron cloub of carbonate ion
-Cation less effect on carbonate ion
-Ionic compound become more stable
-More heat needed to break the bond

-Thermal stability increases

COMMERCIAL USES OF LIMESTONES, CaCO3
i. Fuel industry
ii. Quick Lime
iii. Building materials
iv. Portland cement
v. Antacid
vi. Diet Enrichment

Summary Compound of Group IIA (Oxide) & Questions- TAN SOK JING (A21HP0225)

2022-04-23 07:45:07 UTC

Questions:
1. Dr, I still confuse about the compatible of size in affecting the solubility for Group IA and what is the meaning of the size is compatible?

2. How do we identify whether the element have vacant d-orbital or not? Is that any element starts from period 3 has vacant d-orbital? As I am wondering why saying that potassium is less dense than sodium because of the presence of d-orbital in potassium. The sodium does not have vacant d-orbital although it is in period 3?

Thank you dr.

SUMMARY CARBONATE | NUR ANIS SYAFIQA BINTI ABDUL RASHID (A21HP0132)

2022-04-23 12:55:51 UTC

Summary: Compound of Group IIA (Oxide,MO)

2022-04-23 13:36:59 UTC

Preparation

1. In Industry: Heating carbonate salts of Group IIA

MCO3 -> MO + CO2, where M= Mg,Ca

2. In lab:

MCO3 -> MO + CO2

M(OH)2 -> MO + H2O

M(NO3)2 -> MO + 4NO2 +O2

Physicochemical Properties

· All metal oxides are IONIC except for BeO.

· When the divalent metal ions heated in pure oxygen, they sufficiently polarizing forming peroxide.

From Be to Sr only form monoxide (MO)

Ba forms peroxide, BaO2 under pressure.

In terms of Solubility;

· The solubility of these oxides increases as it goes down the group, from Be to Ba.

· As the increased in the size of the cation, the hydration (HE) as well as the lattice energy (LE) decreased. We called it as (the size incompatibility)

· Comparing the decreasing in LE and HE, if the decreasing of LE is greater than HE the total of dissolution energy will be in the -ve value.

In terms of Melting point;

· The melting point of the monoxides decreases when going down the group.

· When the size of the cation increases from Mg to Ba, the lattice energy will be reduced.

In terms of Basicity;

· All oxides are BASE except for BeO (Amphoteric).

· When there is a major difference in the electronegativity, the metal-oxygen bond becomes more ionic.

· As it shown more ionic characteristics, it becomes more basic.

Summary: Compound of Group IIA (Sulphate)

2022-04-23 15:49:42 UTC

-Metal sulphate molecular formula: MSO4
- reaction of metal salt with H2SO4 produce metal sulphate.

MX + H2SO4 -> MSO4 + HX
*M and X can be change to:
M = BE | X=O
M=Mg | X=CO3
M=Ca, Sr, Ba | Cl

a) Properties:
* sulphate salt exist in hydrated form/ hydrated salt
* hydrated salt (Crystalline salt) loosely attached to certain no. water molecules.
* no. mole hydrated water depends on temperature:
- MgSO4.7H2O: Epsom salt
- CaSO4.2H2O: Gypsum salt
- CaSO4. 1/4H2O: Plaster of Paris

b) Thermal stability
- increases when down the group
- due to decreases polarizing ability in cation.
- size ionic radius bigger when down the group
- size ion increases
- polarizing power decreases
- compound more stable, more heat to decompose to oxide.

*increase stability:
BaSO4> SrSO4> CaSO4> MgSO4> BeSO4

- Solubility depends on lattice energy & hydration energy
- solubility sulphate decreases down the group due to hydration energy decrease with increasing cation size.

*Decrease solubility:
BeSO4> MgSO4> CaSO4> SrSO4> BaSO4

c) Application:
* Epsom salt (MgSO4)
- act as medicine, fertilizer, coagulent for making tofu & as drying agent (anhydrous)

* Gypsum salt (CaSO4)
- act as Portland Cement, plaster, fertilizer in agriculture & chalk

* BaSO4
- use in medicine (Barium meal), given to patient to obtain good quality photograph of digestive tract because it is opaque to X-rays.

That's all my summary, Thank you Dr :)

SUMMARY COMPOUND OF GROUP IIA (SULPHATE)

2022-04-23 15:58:52 UTC

MUHAMMAD HIFZHUDDIN BIN YUSRI (A21HP0091)

Preparation:
For Be:
BeO + H₂SO₄ --> BeSO₄ + H₂O
For Mg:
MgCO₃ + H₂SO₄ --> MgSO₄ + H₂CO3
For Ca, Sr, Ba:
CaCl₂ + H₂SO₄ --> CaSO₄ + 2HCl
SrCl₂ + H₂SO₄ --> SrSO₄ + 2HCl
BaCl₂ + H₂SO₄ --> BaSO₄ + 2HCl

Properties:

Exist in a hydrated form (hydrated salt). The number of mole of hydrated water depends on the temperature.

MgSO4.7H2O : Epsom salt
CaSO4.2H2O : Gypsum salt
CaSO4.1/2H2O : Plaster of Paris

Thermal stability increases down the group due to the decrease in polarizing ability.
BeSO₄ < MgSO₄ < CaSO₄ < SrSO4 < BaSO₄
Solubility decreases down the group

BeSO₄ > MgSO₄ > CaSO₄ > SrSO₄ > BaSO₄Application:

Epsom salt as medicine, fertilizer, coagulant for making tofu and drying agent
Gypsum salt as Portland Cement, Plaster of Paris, chalk, gypsum board and also fertilizer
BaSO4 is used as Barium meal. Barium meal is given to patient on getting a good quality x-ray photograph

SUMMARY : COMPOUND OF GROUP IIA - CARBONATE, MCO3 | YASMIN BINTI AZMAN (A21HP0214)

2022-04-23 16:32:34 UTC

· Carbonate (MCO₃ )

-Exist naturally in the Earth crust.

-Forming minerals (due to insoluble property of the carbonate)

· Preparation (In lab)

#MgC0₃

Mg(NO₃₎₂ + 2NaHCO₃ → MgCO₃ + 2NaNO₃+ H₂O + CO₂

-cant use Na₂CO₃ as it is too basic

#CaC0₃

CaCl₂ + Na₂CO₃→ CaCO₃ + 2NaCl

· Physiochemical Properties

1) Solubility (decreases down the group)

2) Thermal Stability (increases down the group)

#Solubility

(Decreases down the group)

BeCO₃ > MgCO₃ > SrCO₃ > BaCO₃

As we go down the group,

-The ionic radius of cation increases.

-The decrease in lattice energy is small due to the larger size of anion (CO₃^2-). Hence, the size of cation is negligible and does not affect the lattice energy.

-Polarizability (ions) towards water decrease. Thus, less energy is released.

-Hydration energy becomes less negative.

#Thermal Stability

(Increases down the group)

BeCO₃ 3 < SrCO₃< BaCO₃

As we go down the group,

-The ionic radius increases.

-The polarizability decreases.

-The charge density (cation) decreases.

-We need more heat to break the bond between CO2 and metal oxide.

· The Uses Of Limestone (CaCO₃)

-Antacid

-Fuel industry

-Building material

-Solvay Process

-Portland cement

-Diet enrichment

Summary; Compound of group IIA (carbonate)

2022-04-23 16:45:58 UTC

SITI NURFARIESHAH BINTI SUBOH A21HP0199
Group 2: Alkaline Earth Metals and Carbonates (MCO₃)

Beryllium Carbonate (BeCO₃)
Magnesium Carbonate (MgCO₃)
Calcium Carbonate (CaCO₃)
Strontium Carbonate (SrCO₃)
Barium Carbonate (BaCO₃)

Preparation in laboratary
--> MgCO₃

Mg(NO₃)₂ + 2NaHCO₃ --> MgCO₃ + 2NaNO₃ + H₂O +CO₂

--> CaCO₃

CaCl₂ + Na₂CO_{3 -->} CaCO₃+ 2NaCl

The effect of heat on the Group 2 carbonates

All the carbonates in this group undergo thermal decomposition to the metal oxide and carbon dioxide gas. The term "thermal decomposition" describes splitting up a compound by heating it. All the Group 2 carbonates and their resulting oxides exist as white solids.

MCO3(s)→MO(s)+CO2(g)

Down the group, the carbonates require more heating to decompose.

The carbonates become more/increase thermally stable down the group.

:. Thermal Stability BeCO₃ 3 < SrCO₃< BaCO_3
:.Both carbonates and nitrates of Group 2 elements become more thermally stable down the group. The larger compounds further down require more heat than the lighter compounds in order to decompose.

Solubility of the carbonates

The carbonates tend to become less soluble - go down the Group.

Industrial chemical often used, limestone CaCO3,

Sodium Carbonate,soda ash,= mainly obtained by a method named Solvay process by the chemical reaction of limestone (CaCO3) and sodium chloride (NaCl).

2 NaCl + CaCO₃ → Na₂CO₃ + CaCl @

Calcium Carbonate common uses ; in glass, textile, paint, paper and plastic production, to produce ink and sealant. It is also used as a food additive (non toxic), as a drug development and chalk production.

Other
Strontium Carbonate (SrCO₃)

Uses: fireworks, magnets and ceramic manufacture.

Magnesium Carbonate (MgCO₃)

Uses: skin care products, cosmetic,

Barium Carbonate (BaCO₃)

Uses: glass, cement, ceramic, porcelain, rat poison manufacture.

_{:. that's all from me, tq dr :)}

SUMMARY : COMPOUND OF GROUP IIA -( SULPHATE ) MUHAMMAD AMIRUL BIN KHAIRUL NIZAM A21HP0080

2022-04-24 15:12:50 UTC

-Metal sulphate molecular formula = MSO4
-Example CaSO4

PREPARATION
- metal sulphate is prepared by metal salt react with acid , example H2S04

MX + H2SO4 -> MSO4 + HX
M = Be , X = O
M = Mg, X = CO3
M = Ca/Sr/b X = Cl

CaCl + H2SO4 -> CaSO4 + HCl

PROPERTIES
1-Sulphate salts are exist in hydrated form or hydrated salt
2-Hydrated salt loosely attached to certain number of water molecule .
3-Number of mole hydrated water depends on the temperature

MgSO4.7H20 : Epsom Salt
CaSO4.2H2O : Gypsum salt
CaSO4.1/2H2O : Plaster of Paris

4-Thermal stability increase down the group due to the decrease in polarizing ability.
5-Solubility decrease down the group

APPLICATION

EPSOM SALT (MgSO4)
- as medicine , fertilizer coagulant for making tofu and drying agent

GYPSUM SALT (CaSO4)
- manufacture of wallboard, cement, plaster of Paris, soil conditioning, a hardening retarder in Portland cement.

BaSO4
-It is used to increase the density of the polymer by acting as a filler for plastics. Used to test the pH of the soil. Used as a filler or to modify the consistency in oil paints. It is used in imaging of the GI tract during barium meal.

SUMMARY COMPOUND OF GROUP IIA ( OXIDE) - UZAIR LATIF HADI A21HP0207

2022-04-24 21:12:28 UTC

Formula of oxide is MO in compound group IIA.

PREPARATION :
1. In industry by heating carbonate salts of group IIA metals.
MCO_³ -> MO + CO₂2. In laboratory for M ( Mg, Ca)
MCO₃ -> MO + CO₂
M(OH)₂ -> MO + H₂0
M(NO₃)₂-> MO + 4NO₂ + O₂PROPERTIES :
- All metal oxides are ionic expect BeO.
- The divalent metal ions sufficiently polarizing to make peroxide when heated in pure oxygen. Therefore due to size Be to Sr, it can form only monoxide (MO).

SOLUBILITY :
- Solubility of oxides increases down the group due to increasing size of cation. But when the size is increase, the lattice energy and the hydration energy will be decrease.
- BeO < MgO < SrO < BaO

MELTING POINT :
- Melting point of oxides decrease down the group due to increasing size of cation.

BASICITY :
- All oxides are base except BeO.
- Basicity increasing down the group.
- The difference of electronegativity increasing by the more ionic of the metal.

That all from me, tahnk you dr...

SUMMARY COMPOUND OF GROUP IIA : HYDRIDE

2022-04-24 21:35:53 UTC

MUHAMMAD AFIQ BIN KHAIRUL@KHAIRIL ANUAR (A21HP0072)

Hydride has molecular formula which is MH₂.To obtain Hydrides from the IIA element, it can be carried out by the Direct Heating method with H₂. This method should not apply to the Be element. Be need to be in a BeCl₂ state and heated with LiAlH₄.

M(p) + H₂ (g) -> MH₂ (p) ; (M= Mg….Ba)
For Be
2BeCl₂ + LiAlH₄ -> 2BeH₂ + LiCl + AlCl₃Properties :

All metal hydride are ionic compound and contain H- ion except Be
BeH2 are covalent bonding(Polymeric solid) and link by H2 bridge

Reaction :

Reaction with water
MH₂ + 2H₂O → M(OH)₂ + 2H₂ (M= Mg....Ba)
e.g: MgH₂ + 2H₂O → Mg(OH)₂ + H₂ (g)

Thermal stabilization
MH₂ → M + H₂
Mg < Ca < Sr < Ba
Increasing
Thermal stabilization increase down the group IIA.

Neither reaction involves the Be element.