s3_chem_note_3_CaCO3_ENG

Calcium carbonate can be produced from quicklime through two processes in the following

• Adding water > Adding carbon dioxide gas

• adding carbon dioxide gas> Adding water

• Adding water> Heating

• Heating > Adding water

To identify an unknown powder, a student heated the powder in a Bunsen flame. A brick-red flame was observed. When the powder was added to dilute hydrochloric acid, it dissolved without any observable changes. What might the powder be?

• Calcium carbonate

• Sodium carbonate

• Calcium chloride

• Sodium chloride

Which of the following statements concerning limewater is INCORRECT?

• It is colourless.

• It is produced by dissolving calcium carbonate in excess water.

• It is an aqueous solution of calcium hydroxide.

• It becomes milky and then colourless when carbon dioxide is bubbled into it until excess.

When calcium carbonate is strongly heated, a solid is obtained. Which of the following statements concerning the solid is correct?

• It is black in colour.

• It reacts with water to give calcium hydroxide.

• It is calcium hydroxide.

• it is a mixture.

Which of the following methods can be used to distinguish between solid sodium chloride and solid calcium carbonate?

• Testing the solubility of the solids in water

• Observing the colour of the solids

• Adding dilute nitric acid followed by silver nitrate

• Flame test

Which of the following is the correct procedure to change calcium carbonate to limewater?

• Heating calcium carbonate strongly, adding water and then filtration

• Heating calcium carbonate strongly and then adding in plenty of dilute acid     

• Heating calcium carbonate with water and then allowing it to stand for a few minutes

• Heating calcium carbonate with carbonated water

Which of the following word equations correctly shows the reaction that occurs when calcium carbonate is heated strongly in air?

        A.   

        C.    calcium carbonate ® calcium oxide + carbon dioxide

        D.    calcium carbonate ® calcium + carbon dioxide

• calcium carbonate > calcium oxide + carbon

• calcium carbonate > calcium + carbon + oxygen

• calcium carbonate > calcium oxide + carbon dioxide

• calcium carbonate > calcium + carbon dioxide

When carbon dioxide is bubbled into limewater, the solution turns milky. Which of the following substances makes the solution milky?

• Calcium

• Calcium oxide

• Calcium carbonate

• Calcium hydrogencarbonate

Which of the following statements about the reaction between very dilute hydrochloric acid and chalk are INCORRECT?

• A gas that gives a ‘pop’ sound with a burning splint is produced.

• When acidified silver nitrate solution is added to the resultant solution, a white precipitate forms.

• The resultant solution gives a golden yellow flame in the flame test.

• it give out colourless gas

Which of the following tests can be used to test for the presence of carbonate in a compound?

• Heat the compound strongly and then bubble the gaseous product into calcium hydroxide solution.

• Add an acid to the compound and then bubble the gaseous product into calcium hydroxide solution.

• Add an alkali to the compound and then bubble the gaseous product into calcium hydroxide solution.

• Add an acidify silver nitrate solution to the compound and then white precipitate is formed