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How can you determine which sample of shell contains a higher percentage of calcium carbonate?

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How can you determine which sample of shell contains a higher percentage of calcium carbonate?

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Write your names as the Title and then type out the Procedure.
Note: Assume both shells X and Y have the same mass.

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mass of reaction mixture
1)measure the mass of the shells with electronic balance
2)add theshells into the excess hydrochloric acid until no more effervescence is formed.
3)measure the mass of the mixture with electronic balance
4) compare the 2 masses

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Mass loss method

1. Measure the mass of both mussel shells with electronic balance
2. Measure the volume of excess acid
3. Place each shell into excess acid and wait for bubbles to stop forming
4. Filter the mixture and measure the mass of residue which are the shells without CaC03.
5. Calculate mass difference of beginning mass and ending mass and compare
6. The shell with the greater mass difference contains more CaCO3

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Mass of reaction mixture
1. Fill a conical flask with 200ml of hyrochoric acid. Place it on an electronic balance
2. Quickly add the shell 1 and place a cotton wool at the mouth of the flask which is still on the electronic balance.
3 Wait till there is no more effervesence observed and record the mass.
4. Repeat steps 1 to 3 using shell 2
5. Compare the masses recorded to find out which shell has a higher percentage of CaCo3, the one with a lower mass at the end has a higher percentage of CaCo3.

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Mass loss method
1)place the shell into excess nitric acid which is in a conical flask
2)cover the mouth with a cotton wool which alllows gas to escape and prevents the loss in nitric acid
3)measure the mass of the shell and nitric acid once effervescence stops, using an electronic balance
4)calculate the difference in mass
5)do it for both shells
6)the one with the higher mass has lesser calcium carbonate
7)mass difference divided by original mass = %of calcium carbonate

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Mass Of Residue Method
1. Measure mass of shells X with an electronic balance
2. Measure 50 cm cube of hydrochloric acid in a measuring cylinder
3. Add excess acid to the shells until effervescence is no longer observed
4. Then, filter the mixture and collect the unreacted shell residue
5. Measure the mass of the residue using an electronic balance
6. Calculate the percentage of calcium carbonate in the shells by:
%of calcium carbonate=((mass of shells-mass of residue)/mass of               shells)x 100%
7. Repeat steps 1 to 6 for shells Y

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MASS LOSS METHOD
1. Place a conical flask with 100 ml of hydrochloric acid in it and two shells outside the conical flask on an electronic balance.
2. Measure the mass of the experiment setup and record the reading.
3. Place the two shells into the conical flask and cover the mouth of the flask with a cotton wool to allow gas to escape while preventing the droplets of acids from splashing out.
4. Measure the mass of the reaction with the conical flask and record the reading.
5. Find the difference of the total mass before and after the experiment.
6. Use formula difference between the starting and end mass over the mass of the end of experiment and multiply the whole thing by 100%.

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Mass loss method:
1. Using an electronic balance, measure the mass of shell A and 200g of excess HCl in the conical flask.
2. Place the shell into the flask.
3. Place cotton wool at mouth of flask to prevent loss of acid solution.
4. When no effervescence formed, measure the mass of flask with shell A in it using an electronic balance.
5. Repeat steps 1-4 with shell B.
6. Compare the mass of shells A and B

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Method: Measure the volume of the carbon dioxide using gas syringe method

1. Measure the volume of 20cm3 of excess hydrochloric acid used using a measuring cylinder
2. Label both shells A and B respectively.
3. React the shell A with the hydrochloric acid and add a stopper
4. Read the measurement on the graduated gas syringe once there is no more effervescence produced
5. Repeat steps 2-4 with shell B
6. The syringe with a higher volume of carbon dioxide has a higher percentage of calcium carbonate in the shell.
7: :)

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CO₂ method

1. Place calcium carbonate(shell) into excess hydrochloric acid until there is no effervesence.
2. Collect the gas using a syringe and measure the volume of carbon dioxide.
3. Repeat steps 1 and 2 using a different shell
4. The shell with the higher percentage of calcium carbonate will have a larger volume of carbon dioxide produces

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volume of carbon dioxide gas
1) measure 500 ml of excess  hydrochloric acid using a measuring cylinder.
2) place the shell into the excess hydrochloric acid until no more effervescence
3) bubble the produced carbon dioxide into a downward displacement of water through a tube.
4) measure the volume of carbon dioxide produced by the reaction between the shell and the acid.
5) repeat step 1-5 for the second shell.
6) compare both recordings to determine which has a higher percentage of calcium carbonate. The set up producing more carbon dioxide has a higher percentage of calcium carbonate.

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1) Measure the volume of 50cm3 of excess HCl with a measuring cylinder.
2) Add the excess HCl to the conical flask containing  shell X.
3) Measure  the volume of CO2 produced using a gas syringe.
4) Repeat the experiment using shell Y.
5) Compare the two results. The shell that produce more CO2 has a        higher percentage of calcium carbonate.

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MASS OF RESIDUE METHOD

1. Measure the mass of each shell with an electronic balance.

2. Pour excess acid into a conical flask and place the shells inside 1 flask each.

3. Put a ball of cotton wool at the mouth of the conical flasks.

4. When there is no more sign of effervescence, filter the mixtures.

5. Measure the mass of the residue (un-reacted shell) collected using an electronic balance.

6. Use equation, (original-new mass/original mass)x 100%, to calculate the percentage of calcium carbonate in the shells.

7. Compare the results.

8. Be proud of yourself for completing the experiment ! (yay)

9. End of experiment

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Mass of residue method
1. Measure mass of shells using an electronic blance
2. Add 200 ml of excess acid after measuring it with a measuring cylinder to the the shells in the conical flask
3. Filter out the mixture and collect the residue ( shells ) using filter paper
4. Measure the mass of the residue using an electronic balance.
5. Subtract mass of shell after reaction from the mass at the start to find the loss of mass which is the amount of calcium carbonate.
6. Calculate the percentage of calcium carbonate in the shells by:
%of calcium carbonate=((mass of shells-mass of residue)/mass of               shells)x 100%

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1) using an electronic balance measure the mass of the shells before the reaction
2)measure an excess amount of 100ml of Hydrochloric acid
3) add the shells into the hydrochloric acid
4) wait until there is no longer and reaction, effervescence stopped.
5) Filter the mixture and collect the residue which would be the two shells.
6) measure the mass of the shells using a electronic balance
compare them to the original mass of the shells
7) The difference i n mass divided by the orignal mass multiplied by hundred is the percentage of calcium carbonate within the shell.
8) The shell which has a higher difference in mass is the shell with a higher percentage of calcium carbonate.

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Collection of CO2
1) Use an electronic balance to measure mass of shells.
2) measure 20cm3 of excess HCl and add it into the conical flask.
3) React the shells in the acid.
4) Connect the gas syringe to the flask.
5) Wait till there is no effervescence.
6) Read the volume of CO2 in the syringe.
7) Repeat steps 1 to 6 with the other shells.
8) Compare both results to determine which has a higher percentage of calcium carbonate. The shells producing more carbon dioxide has a higher % of calcium carbonate.
;)

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Mass of residue
1. Measure mass of first shell with electronic balance.
2. Place shell into excess hydrochloric acid until effervescence stops.
3. Filter mixture & obtain residue.
4. Measure mass of residue
5. Calculate % of calcium carbonate with mass of residue/mass of first shell x100%
6. Repeat steps 1-5 with second shell.
7. Compare which shell has higher %
8. Do a totally relevant and cool dab unironically to celebrate

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Mass of residue
Procedure:
1.Measure the volume of the excess acid and add it to the shells until no effervescence is observed
2. Filter the mixture and collect the shells as residue
3.Measure the mass of the unreacted shell and calculate the percentage of calcium carbonate
Formula: (mass of original shell - mass of unreacted shell)/mass of original shell x 100%
4. compare percentage of calcium carbonate

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Mass of residue
1. Measure mass of the shell with an electronic balance
2. Place 100ml of excess hydrochloric acid in a measuring cylinder
3. React shell with acid
4. Filter the mixture
5. Collect and measure the residue with an electronic balance
6. Calculate percentage of calcium carbonate by taking mass of residue over mass of shell
7. Repeat step 1-6 for the other shell and compare the reult