Hydrated and Anhydrous Substances

Q.

A substance that doesn't contain water is called___ .substance

Q.

(a) Why does common salt get wet during the rainy season ?

(b) How can this impurity be removed ?

(c) Name a substance which changes the blue colour of copper sulphate crystals to white.

(d) Name two crystalline substances which do not contain water of crystallisation.

Q. Give two examples of hydrated substances.

Q. What is the formula for magnesium sulfate heptahydrate?

1. $MgS\cdot 7H_{2}O$
2. $Mg{\left({SO}_4\right)}_2\cdot 6H_{2}O$
3. $MgS\cdot 6H_{2}O$
4. $Mg{SO}_4\cdot 7H_{2}O$

Q. Which of the following salts has no water of crystallization?

1. Washing soda
2. Blue vitriol
3. Baking soda
4. Gypsum

Q. The compound called microcosmic salt is:

1. $N{a}_{2}HP{O}_4.2H_{2}O$
2. $N{a}_{2}N{H}_{4}P{O}_4.2H_{2}O$
3. $(N{H}_4{)}_{2}HP{O}_4.2H_{2}O$
4. $Na\left(N{H}_4\right)HP{O}_4.4H_{2}O$

Q. On heating 1.763g of hydrated $BaC{l}_2$ to dryness 1.505g of an hydrous salt remained. What is the formula of hydrate ?

1. $BaC{l}_2$$.H_{2}O$
2. $BaC{l}_2$$.3H_{2}O$
3. $BaC{l}_2$$.5H_{2}O$
4. $BaC{l}_2$$.2H_{2}O$

Q. What is the difference between a hydrate and an anhydrate?

1. They are two separate and different compounds.
2. An anhydrate is a hydrate with the 'an' removed.
3. An anhydrate is a hydrate with the water removed.
4. A hydrate is an anhydrate with the water removed.
5. They are different words for the same thing.

Q. Which of the following is an example of hydrated substance?

1. Washing soda
2. Blue vitriol
3. Gypsum
4. All of the above

Q. A salt which changes into liquid state on absorbing water from air is called hydrated salt.

1. true
2. false