Reactions of Carbon and Carbon Dioxide

Q.

Silver carbonate is a white powder. When heated in a dry test tube, it forms solid grey silver and colourless gases namely, carbon dioxide and oxygen ${\mathrm{Ag}}_2{\mathrm{CO}}_3\stackrel{∆}{\to }\mathrm{Ag}+{\mathrm{CO}}_2+{\mathrm{O}}_2$. What conclusions can you draw regarding four substances: silver carbonate, silver, carbon dioxide, oxygen

Q.

A house wife wanted her house to be white washed. She bought 10 kg of quick lime from the market and dissolved in 30 litres of water. On adding lime to the water, she noticed that the water started boiling even when it was not being heated. Give reason for her observation. Write the corresponding equations and name the product formed. [3 MARKS]

Q.

Why does a cake become fluffy after baking?

Q. A compound X is formed when carbon dioxide reacts with sodium hydroxide. The same compound is obtained when baking soda is heated. Identify X.

1. $N{a}_{2}O$
2. $NaOH$
3. $N{a}_{2}C{O}_3$
4. $NaCl$

Q.

When NaCl is mixed with water and carbon-dioxide and ammonia, two products X and Y are produced. On heating X, sodium carbonate is obtained as product. And when sodium carbonate reacts with sufficient water, product Z is formed.

What is X, Y and Z?

1. X = NaOH, Y = H₂O and Z is washing soda

2. X = Na₂CO₃, Y = NH₄Cl and Z = Baking soda

3. X = NH₄Cl , Y = NaHCO₃ and Z = Washing soda

4. X = NaHCO₃, Y = NH₄Cl and Z = Na₂CO₃.10H₂O

Q. Choose the correct option regarding chlor-alkali process:

1. All of the above.
2. $H_2$ is given off at the anode.
3. Brine solution decomposes on the application of electricity.
4. $C{l}_2$ is given off at the cathode.

Q. _________ , a greenhouse gas is released during the decomposition of limestone.

1. Carbon dioxide
2. Methane
3. Ozone
4. Nitrous oxide

Q. Identify X in the below equation.

$CaC{O}_3+HCl\to CaC{l}_2+X+H_{2}O$

1. $O_2$
2. $C{O}_2$
3. $C{l}_2$
4. $H_2$

Q. Which of the following can be used to obtain carbon dioxide?

1. Methane
2. Calcium carbonate
3. Carbon monoxide
4. Glucose

Q.

What visible change is observed when $C{O}_2$ is passed through lime water and that change is due to the formation of which compound?

1. Blue color, $CuS{O}_4$

2. Green color, $CuC{O}_3$

3. Milkiness, $Ca(HC{O}_3{)}_2$

4. Milkiness, $CaC{O}_3$

Q. Complete the given reaction.

$C{O}_2+$ $\to NaHC{O}_3$

1. $N{a}_{2}C{O}_3$
2. $NaOH$
3. $H_{2}C{O}_3$

Q. _________ , a greenhouse gas is released during the decomposition of limestone.

1. Carbon dioxide
2. Methane
3. Ozone
4. Nitrous oxide

Q. What visible change is observed when $C{O}_2$ is passed through lime water? Which compound in the products is responsible for this change?

1. Blue color, $CuS{O}_4$
2. Green color, $CuC{O}_3$
3. Milkiness, $CaC{O}_3$
4. Milkiness, $Ca(HC{O}_3{)}_2$

Q.

Which of the following is a method of preparation of $C{O}_2$?

1. By complete combustion of carbon

2. By action of dilute mineral acids on carbonates.

3. As a by-product from the manufacture of Hydrogen for making ammonia.

4. None of these

Q.

If you blow into a glass of limewater, what is the change in colour you can observe?

1. Brown to colourless

2. Colourless to milky-white

3. Colourless to brown

4. Milky-white to colourless

Q.

Explain, giving one simple example of the following chemical changes

Double decomposition