Class for SSCC1703 - 12/11/2020 Group IA by SHEELA CHANDREN

IRDINA BINTI AZUWIR

irdina01 — 2020-11-12 04:10:14 UTC

Summary Group IA
- Size & reactivity increase, IE decreases down the group
- Exist as ionic compounds (high mp, white except coloured anion, soluble in H2O)
- Metal compounds have diff. flame colour
- Can form covalent compound
- Solubility depends on 2 factors Hlatt and Hsolv.
- 2 phases when dissolving: separation and hydration
- +tive Hsolvn insoluble and vice versa
- Down Process: extract Na & Li
- K, Rb, Cs: red. molten chloride with Na vapour
- Hydrides: prep by M + H2
- Oxides: 3 forms, depend on M, O2, temp.
- Hydroxide: Electrolysis
- Carbonates: Solvay Process
- Nitrates : naturally occur.
- Halides: direct combination of elements
- Hlatt: +tive (dissoc.), -tive (form.)
- Compatible sizes = more -tive Hlatt
- Thermal stability: increases down group (carbonate & nitrate)
- Solubility: compatible sizes = insoluble
- Li anomaly

SITI NOR SYAFIQAH BT MOHAMAD

2020-11-12 04:10:33 UTC

Thank you Dr for today's lesson.
I a get little bit confiuse about today's topic but i will study it again later.I will make more practice to try understand more about this topic.I will ask you if i still dont understand about it dr.

IFFAH IZZATI BINTI AZMAN

2020-11-12 04:11:04 UTC

Thank you dr for today's lecture. I can understand better the solubility of salt after you give lots of example. I have a question about Part 2 hydroxide. The electrolysis process is used to produce sodium hydroxide only or potassium hydroxide also can be produced?

NUR QISTINA IZZATI BT MOHD FITRINAZRIN POON

2020-11-12 04:12:35 UTC

Thank you Dr Sheela for lesson today. So far i have no any problem and question about today topic. Will looking forward for practice about this topic.

ZULFA ANNISA BINTI MOHD NOOR

zulfaa480 — 2020-11-12 04:14:20 UTC

Thank you Dr. for today's lesson . I have so much input received from you but need a some times to understand it and this is my summary about group IA :-
- Group IA known as Alkali metals and it is in a solid state . as going down the group , the size and reactivity increases . It is also very electropositive . Each metals have their own individual colour flame to be used as identification. There are 5 compounds of Alkali Metals which are hydride , oxide , hydoxide, carbonate and nitrate. Each of their compounds have their own physical and chemical properties , preparations and reaction , and industrial processes . I also learnt about nitrates and halides . Thermal stability and solubility increases as going down the group .There are fews anomaly of Lithium from the other Alkali Metals and reasons of diagonal relationship between Lithium and Magnesium .
That's all for my summary . Thank you Dr.

ROSE SYAZWANI BINTI RAMLI

2020-11-12 04:18:12 UTC

What i have learn from today's meeting is that the more compatible ion(same size),the more energy needed to seperate both ions,resulting the lattice energy to be more positive. Vice versa for the less compatible ion(different size).
SUMMARY
-known as alkali metal and in form of silvery solids with low demsity and low mwlting points
-from top to bottom the reactiveness, size and electron shells shielding increase
-in this group IA,all have 1 electron valence
-act as electron donor
-if the lattice energy low,then it is high soluble
-hydrides react violently with water
-Group IA can react with oxygen and form oxide,peroxide and superoxide except Li can only form oxide
-Solvay process is industrially preparation
-Li anomaly

SYED MUHAMMAD KHAIRI BIN SYED NORDIN

2020-11-12 04:19:04 UTC

Summary for group IA
-known as alkali metals
-size increase down the group
become more dense down the group (potassium less dense than sodium)
melting point and IE decrease down the group
exist as ionic compound, normally white colour
-solubility
Hsoln=Hlatt +hsolv
if Hsoln -ve =high soluble
Na and Li metal can be obtain by Down process
K, Rb and Cs metal by reduction using molten chloride with Na vapour

SYAZIEMAH BT JASMANI

2020-11-12 04:19:47 UTC

Thankyou Dr for your expalanation.
Summary Group IA :
- Going down a group reactivity increase and more dense.
- We can know the colour flame of all metal.
- More negative it easier soluble.
- Condition to know the types of oxides are type of metal, amount of oxygen and temperature.
- Solvay process is preparation of sodium cabonate.
- Down a group the solubility for small ion salts increases while bigger ion salt solubility decrease.

I'm still confusing about the part 3 of Group IA. I will learn more to understand this topic.

CHEW ZI KHANG

2020-11-12 04:23:41 UTC

Thank you dr. for your online class today and two pre-recorded class. I had learnt about the elements of Group IA especially for the solubility of the oxides and etc. I had also learnt tat the abnormal characteristics of lithium due to its size. Again, I very appreciate that dr. had discussed about the question in quiz and also past year question which absolutely help us a lot on the technique of answering question. Lastly, i would like to thanks again dr.

NURUL NASYRAH BT SAHAR

2020-11-12 04:28:04 UTC

Thank your dr for the explaination today. what i have learnt from group IA are
-reactivity are increases down the gp as the size increases.
-can form ionic and covalent bond
-solubility depends on lattice and hydration energy
-compund of alkali metals:
hydrides,oxides(monoxide.m2o.,peroxide.m2o2.,superoxide.mo2.),hydroxide,carbonate(m2co3)-solvay process, nitrates-more negativity,more stable and easy to formed,more compatible solubility decreases hard to break the bond,incompatible solubility increases cause less energy needed to break bond.

i hope i can more understand about this topic and do more exercises.

MUHAMMAD DANISH BIN MOHD ARIF

2020-11-12 04:28:48 UTC

Thank you Dr for today's class and the two previous video about group iA. Here are some of my summary from this topic and I got no question for now.
-Group IA increase in their reactivity as go down the group because of the addition number of shell added from Li to Fr
- React with water and form alkali and H
- the top three ( Li, Na, K ) float in water because of their density are lower than water while ( Rb, Cs, Fr) not floating in water
- The ionization energy decreases down the group
- The electron affinity decreases down the group
-The size increase down the group
- the shielding effect increase down the group
- Consist of 5 compounds in group iA:
i) hydrides
ii) oxides
• monoxide
• peroxide
• superoxide
iii) hydroxide
iv) carbonate
v) nitrate

HEMLYN HENDRY

2020-11-12 04:33:49 UTC

Thank you for today's class and previous lecture videos dr, although I do have difficulties understanding today's topic and I will try my best to understand it better. As for the summary, I have learnt that group 1 metals have 1 electron in their outer shell and the reactivity increases down the group due to the increase in size. The physical properties are such as soft metal with silvery colours, good thermal electrical conductors. There are 5 compounds of alkali metals such as hydrides, oxides, hydroxides, carbonate and nitrate. NaOH and KOH are prepared via Industrial process which are electrolysis whereas sodium carbonate is prepared via solvay process.

Siti Hadijah binti Muslimun

2020-11-12 04:36:30 UTC

Thank you Dr for today’s explanation and two pre-recorded class. This topic a bit tough for me but I will try my best to understand it. So what can I conclude for this whole topic is :

- why potassium is less dense than sodium

- solubility and extraction (down process)

- oxides- type of metal, amount of oxygen & temperature
- industrial process for naoh & koh – electrolysis (Kellner-solvay cell)
- industrially preparation for na2co3 – solvay process (ammonia-soda)

- halides – direct combination of elements (hlatt & hf & hsoln)

- thermal & solubility of salt of group IA

- why lithium is different from other element in group IA

Nurhanis Khaliesah Binti Mohamad Zamani

2020-11-12 04:46:11 UTC

Thank you Dr for today's class. This is my summary for group IA:
- also known as alkali metals
- reactivity, density and atomic size increases going down the group
- ionisation energy and electron affinity decreases going down the group
- consists of 5 compound which are hydrides, oxides, hydroxide, carbonate and nitrate
- hydrides can be prepared from metal and H2 gas
- hydroxides can be formed by electrolysis
- sodium carbonate can be prepared through Solvay process
- solubility of small ions salt increase down the group
- solubility of bigger ions salt decrease down the group
- thermal stability for carbonate and nitrate increase down the group

SAHIZANZAIHAN BIN ISMAIL

sahizanzaihan114 — 2020-11-12 04:52:49 UTC

Thank you for today's lecture dr. Its quite hard for me to understand especially in today's part. I just need to read more to understand it. So here is my summary :

Group IA
1) Physical Properties
-soft and easily to cut off
-have low melting point and densities
-form white oxides with oxygen
-good conductor of heat and electricity
-shiny and silvery colour

2) Reactivity increases down the group due ro the increasing size of atom

3) The density also increases down the group while the melting point is decreased

4) Chemical Properties
with O2 - burned fiercely and produce a coloured flame
with H2O - react more vigorous when its goes down the group and creates more heat
with acid - very reactive and H2 is evvolved and formed salt
with alkali - H2 gas produced
with halogen - formed halides

5) Application
Lithium - Lithium batteris, as reducing agent(LiAlH4)
Sodium - Vapour in street lamp, alloy used as coolant, flavouring food (NaCl)
Potassium - soft-liquid soap (KOH), fertelizers (KOH,KNO3), metal extraction (KCN)

6) Hydrides
- can be prepared from metal and H2 gas
- formed as ionic crystal and colourless

7) Oxides
- Li2O doest not exist as peroxide and superoxide

8) Hdroxides
- can be prepared by electrolysis (Kellner-Solvay cell)
- used in soap industry, as bleaching agent

9) Carbonates
- solvay process

10) Nitrates
NaNO3 - used as fertelizers, explosives
KNO3 - used in manufacturing

11) Halides
enthalpy of formation
- less negatives from F- to I-
- down the group, F- less negative

12) Solubility
- the more (-ve) enthalpy of dissolution, more soluble the salt
- different ionic radii, the more soluble

SITI NAZURAH BINTI NAZARUDDIN

2020-11-12 05:05:11 UTC

Thank you for today's class Dr. however due to the poor internet connection, its a bit difficult for me to understand today's lesson. i will try my best to understand it once you uploaded the recorded video. but here is my summary for part 1 & 2 of group IA:

-its specific family name is alkali metals.
-increase in their reactivity from top to bottom
-density increases from top to bottom
-soft metal with silvery color
-good thermal/electical conductor
-solubility of their ions depends on 2 factor which is latt energy and hyd energy
-we also learn about 5 compounds of alkali metals which is Hydrides, Oxides(monoxide,peroxide,suoeroxide), Hydroide, Carbonate and Nitrate. and learn about their uses and reaction and application.

LIANA FAQIHAH BINTI MOHD JAFFRI

2020-11-12 05:13:24 UTC

Thankyou dr for today's explanation. Here are some summary from me about group IA :

Down the group
-the reactivity increases because electron farther away from nuclues.
-density become more dense
-IE decrease
-melting boint decreases
-electron affinity decreases

Soulibility depends on :
-Lattice energy
-Hydration energy

Compound of alkali
i) Hydrides :
-prepared directly from metal and H2 gas -----> saline hydride
-react violently with water
MH(s)+H20(l)--->MOH(aq)+H2(g)
-reaction with alcohol -->alcoholate
MH(s)+ROH(I)---->MOR+H2(g)
-reaction with liquid----->amomonia
MH(s) + NH(l)---->MNH2(am)+H2
-Reaction with oxygen
2MH+O2---->M20 + H2
-Uses : As reducing agent ,as source of hydrogen , as fuel
ii) Oxides :
-Monoxides
-Peroxidees
-Superoxides
iii) Hydroxides
-Electrolysis
-Uses: obtaining pure Al2O3 , bleaching agent , manufacture of battery
iv) Carbonates
-Industrial preparation (solvay process involves ammonia absorber tower ,Limestone Furnace,Ammonia supplier tower and carbonate conveter
v) Nitrate (NaNO3, KNO3)
vi) Halides
-Form by direct combination element
-Solubility
1) When two compound have a different size (big and small) , the bonding become incompatible , so less energy needed and less electropositive . Hence solubility increases .
2) When two compound have a same size , the bonding become compatrible , so more energy needed and more electropositive . Hence solubility decreases.

I'm sorry dr for the previous sufficient summary because i thought i only need to summarize the lesson when we are in sychronous classes. I already edit it and sorry again Dr . Thankyou .

SITI RAIHANAH BINTI ROSLAN

2020-11-12 05:29:32 UTC

Thankyou Dr for today's explanation. please make more games in kahoot cause i enjoy it just know !! also i can recall about previous recorded class about group IA which is going down the group, the reactivity increases. For me it's quite challeging to understand this topic especially the thermal stability. i think i need some times to rewatching today recorded video to makes me more understand. i think it might help me.

Summary for group IA(Alkali Metal)

going down the group :
- Reactivity increases, electron farther away from nucleus, the pull is less and the electron in outershell lose easily.
- Atomic radius increases as more orbital is added.
- Melting and Boiling point decreases
- Density increases

Solubility Factors :
1) Lattice Energy
2) Hydration Energy

Compounds of Alkali Metal :
1) Hydrides
- prepared by Metal and H2 gas
- react violently with H2O
- react with alcohol to form Alcoholate
- react with liquid ammonia to form amide
- react with oxygen to form oxide
- reducing agent to produce H2 gas. (NaBH4) more selective than LiAlH4

2)Oxides (Monoxide, Peroxide, Superoxide)

3) Hydroxides
- Electrolysis (Kellner-Solvay Process)
- Saponification

4) Carbonate
- Solvay Process

5) Nitrates

6) Halides
- Enthalphy of Formation
less (-ve) for F-
more (+ve) for Cl-, Br-, I-

Thermal Stability
- oxianion salts are stable because of high electropositive charge.
- themal stability of carbonate and nitrate increases down the group.

Solubility
- more (-ve) enthalphy soloution, more soluble

EMERALDISYAH ALIFIA WISAKSONO

wisaksono — 2020-11-12 05:32:32 UTC

Thank you Dr for today's lecture, there are a lot of materials to cover so to me it's quite a challenging topic to understand, but never say never. Below is my summary of the whole topic, tried not making it too long - aka alkali metals - going down the group, the densities increases (except potassium) & lower melting points - going down the group, the reactivity increases because the electrons are farther away from the nucleus - + water to produce alkali & hydrogen - easily cut, soft metals - good heat/electrical conductors - can identify the metal according to the flame colors - solubility depends on lattice energy of the salt & hydration energy - endothermic=difficult to dissolve / exothermic=easily dissolved - smaller size->bigger ionic charge->stronger bond between ions & solvent=more energy released - extraction of Na/Li & K/Rb/Cs - down cell - application of Li, Na, K - 9 of their chemical properties - preparation & physical properties of hydrides - hydrides' reaction with water, alcohol (alchoholate), liquid ammonia (amide), & oxygen (oxide) - uses of hydrides= reducing agent, source of H gas, fuel - forms of oxides; monoxide, peroxide, superoxide, their properties, reactions, & uses - lab preparation of hydroxide - industrial process, electrolysis, & uses of NaOH - the Solvay Process & why K2CO3 can't be prepare by Solvay Process - nitrates (NaNO3, KNO3) & halides Lattice dissociation & formation enthalpies - oxianion salt; NO3-, CO3-2, OH- stable because of high electropositive charge - thermal stability of carbonate & nitrate increases going down the group - the more negative a solution=more soluble - anomaly of Lithium & the diagonal relationshiop between Li & Mg

TAN JING XUAN

2020-11-12 06:09:40 UTC

Thank you dr for the synchronous class today. I need some time to understand thoroughly in this topic since there are so many subtopics that require understanding but not memorizing only. Here is my summary on this topic:
1. Alkali metals are reactive and have an odd number of electrons.
2. The solubility of ions depends on lattice energy and hydration energy.
3. Down cell is for Na and Li metals only.
4. Lattice formation enthalpies are always negative.
5. Hsoln=Hlatt+Hsolv
6. The more -ve Hsoln, the more soluble the salt.
7. Compound that contain ions with widely different radii are soluble.

YEE SHI WEE

2020-11-12 06:12:31 UTC

1. Hlatt
(a) When ionic compound dissolved in water:
Hsoln=Hlatt+Hsolv
((i)) Separation of free ions
-require energy Hlatt (+ve)
-higher Hlatt, harder to separate, difficult to dissolve
((ii)) Hydration
-release energy Hsolv (-ve)
-smaller ionic size, stronger pull, more energy release, higher Hsolv
(b) When forming halides
Hf=Hsub+HIE+Hdis+HEA+Hlatt
((i)) Forming bond between 2 ions
-release energy Hlatt (-ve)
-decrease down the group
-more -ve, more stable, less soluble

2. Hf
(a) Cl- to I-
-Hf becomes less -ve, atomic size increase, weaker nucleas pull, less stable
(b) Going down Group IA
-Hf (F-) becomes less -ve, atomic size increase but F- ion smaller, less compatible, more soluble
-Hf (Cl-, Br-, I-) becomes more -ve, atomic size increase, similar attraction & reputation, more compatible, less soluble
(c) Hf more negative, less soluble

3. Thermal & solubility
(a) Compound that contains ions with widely different radii are more soluble (compatibility)
(b) Small ions (OH-, F-, CO32-)
-Solubility increase down the group
-increasing Hlatt (separate)
-decreasing Hsolv (form aqueous)
(c) Big ions (SO42-, I-)
-Solubility decrease down the group

4. Anomaly of Li
-Exhibit covalent character
-Can only form normal oxide
-The only Group IA metal can form nitride
-CO32-, PO43-, F- low solubility in water (small ionic size, strong pull, high compatibility)
-LiNO3 decomposes directly to oxide
-LiH very stable towards high temperature
-Cant form stable alum
-diagonal relationship with Mg

QUESTIONS:
1. Why do other alkali metals cant form nitride?
2. Why do we use Solvay Process to prepare Na2CO3 instead of hydrolysis?

WAN NUR ANIS FAQIHAH BINTI WAN MAT

2020-11-12 07:08:05 UTC

Thank you Dr for IA Group explaination.Here is some that I can summarize from IA Group.
-Fr is a radioactive and their properties are hard to study so only learn Li to Cs
-Nacl and LiCl can be prepared by Down Process Cell
-K cannot obtained by electrolysis of KCl as melting point of KCl>K and K also dissolves in molten salt
-Applications of Li, Na and K need to be remember.
-Chemicals properties of alkali group reacts with water, halogen and ammonia
-Hydrides can be prepared by 2 ways which is directly from metal & hydrogen gas form saline hydrides and reaction between alkali group in a flow hydrogen gas form hydrides and metal oxide
-compound of oxygen (monoxide, peroxide and superoxide)
-Hydroxide be prepared by laboratory and industrially,electrolysis (NaOH and KOH)
-preparation of NaOH in industrial, graphite (anode) and mercury (cathode)
-at cathode Na+ reduced instead of H2O even H2O more electropositive due to voltage of hydrogen gas
-NaCO3 be prepared by Solvay Process (net process is exothermic), one of application of NaCO3 is Borax
-K2CO3 cannot be prepared through Solvay Process
-NaNO3 and KNO3 used in fertilizer and explosive
- Halides flourine has higher entalphy of formation but become less negative from LiF to KF(down the group) due to increase in radius of metal ion
-entalphy of formation of bromine,chlorine and iodine more negative
-solubility of halides depends on their lattice energy
-Lithium in an anomaly due to its small size and electronegativity

SITI KHADHIJAH BINTI NASIR

2020-11-12 07:10:29 UTC

Thank you dr for today class. i think i need some time to understand today topic. i will try to catch up once you uploaded the video.
summary for today is :
- There are 5 compound of alkali metal (hydrides , oxides , hydroxide, carbonate, nitrate)
-Down the group reactivity will increase
-solubility depends on lattice energy and hydration energy
- there are diagonal relationship between Li and Mg due to similar atomic size and electronegativity

Ch'ng Zi Long

2020-11-12 07:28:04 UTC

Thank you dr for whole teaching slides and video. I learned a lot about Group IA alkali metal. Below is my summary:
1) reactivity increase down the group as the atomic size increase and thus decrease in ionization energy. Electron is more easily release by the atom.

2) each element in Group IA has its own specific colour of flame.

3) Hsoln=Hlatt+Hsolv
The more negative the value of Hsoln, the more soluble the compound in water.

4) Group IA element can from hydrides, oxides(monoxide, peroxide, superoxide), hydroxide, carbonate and nitrate compound.( need to memorise each reaction and process)

2020-11-12 07:31:29 UTC

Hsoln=Hlatt+Hsolv

WOO JOO LEONG

2020-11-12 07:48:30 UTC

Thank you Dr for the class and explanation. This is my summary on Group IA, we learned:

1) Physical properties , general properties and extraction of group IA elements

2) Preparation of Group IA Hydride, Use of Hydride and reaction of hydride

3) Monoxide, peroxide and superoxide of group IA and it's reaction with h20 and the use of oxide

4)Preparation of hydroxide, manufacture NaOH and use of NaOH.

5) Thermal & solubility of salt of group IA

Question:
1) Do we need to memorize the application of each element?
2) In preparation of LiOH, why we can't use Ba(OH)2 same as other element to react with LiCO3?

AISYAH BINTI MASHURE

aisyahm1 — 2020-11-12 08:27:37 UTC

Thankyou Dr for today's lesson
. I need to take more times to understand for part III later via recorded vd. So for the group IV

1)Physical properties : reactivity, size and density increase,
IE, EA, and mp decrease

2)general properties - identify by color flame.
Solubility depend on lattice energy and hydration energy.
High lattice energy : insoluble

3)extraction
Na and Li : down process (molten state)
K, Rb, Sc : reduction molten chloride w/Na(g)

4)Compounds
a) Hydride (ionic crystal, colourless)
*Prepare
metal +H2
IA oxide +H2
b) oxides
*OXIDE
*PEROXIDE
*SUPER POROXIDE
To identify
i) look type of metal
ii)look amount of oxygen
iii) temperature
c) Hydroxide
Industrial
#NAOH-KOH, electrolysis (Brine)
d) carbonates,
*Na2CO3, Solvay process(Brine, CaCo3, NH3)
*K2CO3, Electrolysis KCl
e)Other oxosalt
*nitrates
*halides
- stable(lattice energy more-ve)

5)Thermal stability and solubility
a) Thermal stability - oxanion salt stable - high electeopositive charge
b) Solubility - compatible size
(more-ve enthalpy solution :enthalpy lattice
6)anomaly Li
7)diagonal relationship Li-Mg

TAN SIN JOE

2020-11-12 13:57:23 UTC

Thank you Dr.Sheela foor today's lecture.
Here's my summary:
1. Reactivity, melting points, IE, EA increases down the group, while density increases down group..
2. More dense(m/V) going down group except potassium which reach 3d orbital with increase in mass is smaller than increase in volume.
3 Hsol=Hlatt + Hsolv/hyd
if Hsoln+ve (Hlatt high), exothermic: insoluble
if Hsoln-ve (Hsolv high), endothermic: easily soluble
4. Extraction: electrolysis(NaCl/LiCl molten)
Reduction of molten chloride with Na vapour (K, Rb, Cs)
5. Reducing agent: LiAlH4, NaBH4
6. Only Li, Na can form monoxide directly
Only Na can form peroxide directly
7. Hlatt:
solubility-always +ve(need E to break bond)
formation-always -ve(release E when elements come together)
8. Li: small ionic radius -> can't completely share e- -> exhibit covalent bonding; has diagonal relationship with Mg

Questions:
1. Note Part1: Extraction
e.g: KCl(l) + Na(g) -> NaCl(s) + K(l)
according to reactivity series, K is more reactive than Na, in this case Na can reduced K from Cl, is it because the compatibility of Na and Cl?
2. Note Part3: Halides
F- to I-: Hf becomes less -ve due to increase radius of the anion and Hlatt becomes negative.
Is this Hlatt means energy release when bonding? If yes, Is the less negative means there is less energy released during bonding?

NUR HANISAH BINTI AZMAN

2020-11-12 16:22:23 UTC

Thank you dr for the class today!

Summary:

· Group IA that also known as alkali metals

· As go down the group, reactivity, orbital, quantum number increase

· Physical properties

o Soft metal

o Electric conductor

o Atomic radii, reactivity, density increase down the group

o IE, EA , melting point decrease down the group

· Solubility

o Depends on lattice energy and hydration energy

o Separation of free ion and hydration process occur

o AHsoln = AHlatt + AHsolv

· Compound of alkali metal

o Hydrides

o Oxides

o Hydroxide

o Carbonate

o Nitrate

· Industrial process

o Electrolysis

o Solvay process

· Termal & solubility

o Compound that contain ions with widely different radii are soluble

o The more negative AHsoln is, the more soluble the salt

-I’ve to repeat the video as im a bit slow in understanding especially on solubility part (cry). And im sure i’ve many other questions to ask you soon hehe.

NURFATINI NASUHA BINTI MOHD NAIM

2020-11-13 05:29:11 UTC

Thank you Dr for the the explanation of IA Group.
Summary:
1. Down the group, density increases. Reactivity increases from Lithium to Cesium.

2. Colour of flame. Application of IA Group. Physical and Chemical Properties.

3. Compounds of IA Group: Hydrides, Oxides, Hydroxide, Carbonates, Other Oxosalts.

4. Halides (MX)

5. Thermal solubility, Solubility

6. Anomaly of Lithium

7. Diagonal Relationship (Li-Mg)

NAURAH AFNAN BINTI KAMARUDIN

2020-11-13 13:06:43 UTC

Thank you Dr.sheela for the lecture.
Summary;
1)Physical properties
-electrical conductor
-melting point decrease
-density increase
-ionization energy decrease
-EA decrease
2)Solubility(depends lattice energy,hydration energy)
3)Compound of alkali metal
-HYDRIDE(form saline hydride,reaction between group IA oxide,reducing agent produce H2,fuel)
-OXIDE(monoxide,peroxide,superoxide)
-HYDROXIDE
eleectrolysis(industrial process)
Espr(tendency to be reduced)

-CARBONATE(industrially preparation--solvay process(brine CaCo3,NH3)

-NITRATE(NaNo3 use for fertilizer,KNO3 used in explosive and firework)

-HALIDES
-lattice dissociation enthalpies always -ve
-lattice formation enthalpies always +ve(become less negative due to increase radius of the anion)

SITI MASYITHAH BINTI MOHAMAD JAN

2020-11-14 03:09:30 UTC

Thank you Dr for your well explaination . I repeated watching your video to understand.For summary:
1) the 5 compounds of alkali
2) reactivity , melting points increasing by going down the group.
3) calculation about lattice energy
4) physical and chemical properties of group IA

HANIS SAFIYAH BINTI MOHD AMIN

2020-11-14 03:15:52 UTC

thank you for your explanation Dr. I am sorry for submit this summary late. it takes me a while to understand the flow and understand it better.
For summary :
1) there are 5 compound of alkali metal which is hydrides, oxides, hydroxide,carbonate and nitrate.
2) for each compound there are a lot of reaction which is reaction between the metals and water, alcohol etc that i need to know and master with.
3)there are also an industrial process to produce NaOH, KOH, Na2CO3 and etc
4) part for thermal and solubility are confusing but for what I understood, the solubility are depands on the size of metals and also how the atom size different form one another. also can different it by look at the amount of entalphy of dissolution . the more the entalphy of dissolution become negative, the more the compunds will soluble in water

I am sorry again Dr. This wont happen again

Puteri Farisah Balqis Binti Erwan

2020-11-15 07:30:51 UTC

Thank you Dr for the explaination. Im sorry for submit this late because I want to understand first this topic.
Summary :
1) There are 5 compounds of alkali metal.
2) A lot of reaction that we learn and must to remember for each compound such as their preparation and uses.
3) How to calculate the lattice energy from haber cycle.
4) Thermal and their stability, how to determine from the compound that comparable or not.

Foo Sze Ting

2020-11-15 08:41:53 UTC

Thank you Dr. for your clear explanation on the topic.
Summary of the topic:
1) Alkali metals are silvery solids with low densities and low melting points. Their reactivity increases as going down the group.
2) The alkali metals become more dense as going down the group but potassium is less dense than sodium.
3) Alkali metals are extremely reactive. It exists as ionic compounds with other elements. It has very high melting points. It is normally white in color. It is soluble in water.
4) When an ionic compound of M+ X- dissolved in water, the following process occur:
a) Separation of free ions in gas phase
b) Hydration
5) The smaller the size of the ions, the bigger the ionic charge. The stronger the bond between ions and solvent. Therefore more energy is released.
6) Compounds of Alkali Metals have 5 types which are Hydrides, Oxides, Hydroxide, Carbonate and Nitrate.
7) Solvay Process
8) Oxanion salt are stable because of the high electropositive charge.
9) Anomaly of Lithium from other alkali metals

Low Jin Wei

2020-11-15 09:18:09 UTC

Thank you dr for the great explanation on this chapter which is Alkali metals.
For summary
1) we learnt about the electron configuration of alkali metals,trend in density( lithium,sodium and pottasium will float on water ),general and physical properties
2)We got some compounds of alkali metals which is hydrides,oxides,hydroxide,carbonate and nitrate
3) We also learnt about their uses for example hydrides is using as a source of hydrogen gas and fuel
4) oxides in the form of monoxide, peroxide and superoxide
5)the process of solvay process,supplier tower and their application

SITI AINA AISHAHA BINTI AZIZAN

2020-11-15 09:22:10 UTC

Thak you dr for the good explanation. Here is the summary for Group 1A

1) Alkali metal is the silver solid with low densities and low melting points. It react with water to produce H2 and metal hydroxide.
2) When we go down the group, the reactivity, softness and density will increase while melting and boiling point will decrease as we go down the group.
3) There are 5 compounds of alkali metal which are hydrides, oxides, hydroxides, carbonates and nitrates.
4) The industrial processes are Solvay process and Electrolysis
5) Application:
-Lithium as batteries
-Sodium in the street light (yellow glow)
-Potassium for production of soft-liquid soap
6)Thermal stability:
-Oxianion salt are stable bcs of the high electropositve charge.
-It will increase as we go down the group.
7)Solubility:
-Solubility depends on: (Lattice energy of the salt, Hlatt and hydration ener, Hsolv)
-When ionic compound M+X- dissolve in water:
*the separation of free ion in gas phase (Hlatt +ve)
*hydration/solvent towards free ions involves release energy--->hydration/solvent (-ve)
-The more negative Hsoln, the more stable salt
-Compound that contain ions with widely different radii are soluble.
8)Lattice dissociation enthalpies are always +ve (to give energy to break up) and lattice formation enthalpies are always -ve
9)More competible, more harder to dissoluble bsc more energy is needed in order to it soluble and separated into separate ions.