Uses of Calcium Carbonate

Q.

Find the total number of protons in 10g of calcium carbonate $\left({\mathrm{CaCO}}_3\right)$.

Q. Gypsum is added in the Final stages of preparation of cement . Why ?

Q.

What does chloroform give when exposed to air and sunlight?

Q.

Write the chemical equation for heating calcium bicarbonate.

Q.

Write the balanced chemical equation for the following reaction:

Copper chloride using Copper carbonate.

Q.

Give two uses of quick lime.

Q.

Calculate the number of particles in 46 g of sodium atoms.

Q.

Calcium oxide is also called lime or quicklime.

1. True
2. False

Q.

What is the super-phosphate of lime?

Q.

Anhydrous copper sulphate turns ____________ on the addition of few drops of water.

Q.

Sulphates and chlorides of magnesium and calcium cause temporary hardness of water.

1. True
2. False

Q.

Name the gas which is evolved on heating baking soda.

Q.

By giving example define thermal dissociation reaction.

Q.

Give a balanced equation for the following conversation

(E). Magnesium bicarbonate in temporary hard water to magnesium carbonate by boiling

Q. Choose the correct statements regarding Calcium carbonate?

1. Can be obtained by passing carbon dioxide through slaked lime.
   
2. It is a white fluffy powder, insoluble in water.
3. All of the above.
4. Can be obtained by the addition of sodium carbonate solution to $CaC{l}_2$

Q. A solid compound ${}^{\prime }{X}^{\prime }$ on heating gives $C{O}_2$ gas and a residue. The residue mixed with water form ${}^{\prime }{Y}^{\prime }$. On passing $C{O}_2$ it turn milky and in excess of $C{O}_2$ through ${}^{\prime }{Y}^{\prime }$ in the water, a clear solution ${}^{\prime }{Z}^{\prime }$ is obtained. On boiling ${}^{\prime }{Z}^{\prime }$ compound ${}^{\prime }{X}^{\prime }$ is reformed. The compound ${}^{\prime }{X}^{\prime }$ is :

1. $K_{2}C{O}_3$
2. $Ca(OH{)}_2$
3. None of the above
4. $CaC{O}_3$

Q.

Explain giving reasons:

Gypsum is used in the manufacturing of cement.

Q.

Dolomite is a mineral of

1. Both magnesium and Calcium

2. Aluminium

3. Magnesium

4. Calcium

Q.

What type of silicate is talc?

Q.

Three elements X, Y and Z crystallise in a cubic solid with X at corners, Y at body centre and Z at the face centres of the cube, then the formula of the solid is

1. XYZ₃

2. X₃YZ

3. XYZ

4. XY₃Z

Q.

A white substance having a strong smell of chlorine is used to clean a water storage tank. Identify the substance. Give its chemical name and write the chemical reactions for its preparation.

Q. Calculate the total number of protons in $10$ gms of Calcium Carbonate ($CaC{O}_3$)

Q.

Give a balanced chemical equation to prepare copper chloride using copper carbonate.

Q.

Compute the difference in masses of one mole of each of aluminium atoms and one mole of its ions. (Mass of an electron is 9.1×10^-28 g).

Which one is heavier?

Q.

An adulterant of Arhar (Tuhar) dal is

1. Brick powder

2. Metanil yellow

3. Kesari dal

4. Gram dal

Q.

When copper sulphide is treated with hydrogen chloride, it gives off a foulsmelling gas H₂S.

Q.

1. Plaster of paris, dead burnt plaster

2. Dead burnt plaster, plaster of paris

3. Plaster of paris, mixture of gases

4. CaO and plaster of paris

Q. What happens?

Q.

Bleaching powder is prepared by passing ${\mathrm{Cl}}_2$gas over/into

1. Solid $\mathrm{CaO}$at room temperature

2. Limewater at an elevated temperature

3. Solid $\mathrm{Ca}{\left(\mathrm{OH}\right)}_2$at room temperature

4. Solid $\mathrm{Ca}{\left(\mathrm{OH}\right)}_2$at an elevated temperature

Q.

Hydrogen sulfide (H₂S) on reacting with an aqueous solution of metal salts converts them to ---------------