1
What is a symbol? What information does it convey?
Solution
2
Why is the symbol S for Sulphur, but Na for Sodium and Si for Silicon?
Solution
3
Write the full form of IUPAC. Name the elements represented by the following Symbols: Au, Pb, Sn, Hg
Solution
4
If the symbol for cobalt, Co was written as CO. What would be wrong with it?
Solution
5
What do the following symbols stand for?
a) H b) H2 c) 2H d) 2H2
Solution
6
What is meant by atomicity? Name a diatomic element.
Solution
7
a) Explain the terms valency and variable valency.
b) How are the elements with variable valency named? Explain with an example.
Solution
b) How are the elements with variable valency named? Explain with an example.
Solution
8
Give the formula and valency of
a) aluminate
b) chromate
c) aluminium
d) cupric
Solution
a) aluminate
b) chromate
c) aluminium
d) cupric
Solution
9
a) What is a chemical formula?
b) What is the significance of a formula? Give an illustrate.
Solution
b) What is the significance of a formula? Give an illustrate.
Solution
10
What do you understand by following terms?
a) Acid radical b) Basic radical
Solution
a) Acid radical b) Basic radical
Solution
11
Select the basic radical in the following compounds
a) MgSO4
b) (NH)2
c) Al2(SO4)3
d) ZnCO3
e) Mg(OH)2
Solution
b) (NH)2
c) Al2(SO4)3
d) ZnCO3
e) Mg(OH)2
Solution
12
Write the chemical formulae of sulphates of Aluminium, Ammonium and Zinc.
Solution
13
The valency of element A is 3 and that of element B is 2. Write the formula of the compound formed by the combination of A and B.
Solution
14
Match the following
Solution
| Compound | Formula |
|---|---|
| Boric acid | NaoH |
| Phosphoric acid | SiO2 |
| Nitrous acid | Na2CO3 |
| Nitric acid | KOH |
| Sulphorous acid | CaCO3 |
| Sulphuric acid | NaHCO3 |
| Hydrochloric acid | H2S |
| Silica (Sand) | H2O |
| Caustic soda (Sodium Hydroxide) | PH3 |
| Caustic potash (Potassium hydroxide) | CH4 |
| Washing soda (Sodium carbonate) | NH3 |
| Baking Soda (Sodium bi carbonate) | HCl |
| Lime stone (Calcium carbonate) | H2SO3 |
| Water | HNO3 |
| Hydrogen Sulphide | HNO2 |
| Ammonia | H3BO3 |
| Phosphine | H3PO4 |
| Methane | H2SO4 |
15
Write the basic and acidic radicals of the following and then write the chemical formulae of these compounds.
a) Barium sulphate
b) Bismuth nitrate
c) calcium bromide
d) Ferrous sulphide
e) Chromium sulphate
f) Calcium silicate
g) Stannic oxide
h) Sodium Zincate
i) Magnesium phosphate
j) Sodium thiosulphate
k) Stannic phosphate
l) Nickel-bi-silphate
m) Potassium mangnate
n) Potassium ferrocynide
Solution
a) Barium sulphate
b) Bismuth nitrate
c) calcium bromide
d) Ferrous sulphide
e) Chromium sulphate
f) Calcium silicate
g) Stannic oxide
h) Sodium Zincate
i) Magnesium phosphate
j) Sodium thiosulphate
k) Stannic phosphate
l) Nickel-bi-silphate
m) Potassium mangnate
n) Potassium ferrocynide
Solution
16
Write chemical names of the following compounds:
a) Ca3(PO4)2
b) K2CO3
c) K2MnO4
d) Mn3(BO3)2
e) Mg(HCO3)2
f) Na4Fe(CN)6
g) Ba(Cl3)2
h) Ag2SO3
i) (CH3COO)2Pb
j) Na2SiO3
Solution
a) Ca3(PO4)2
b) K2CO3
c) K2MnO4
d) Mn3(BO3)2
e) Mg(HCO3)2
f) Na4Fe(CN)6
g) Ba(Cl3)2
h) Ag2SO3
i) (CH3COO)2Pb
j) Na2SiO3
Solution
17
Give the names of the following compounds
a) KClO
b) KClO2
c) KClO3
d) KClO4
Solution
a) KClO
b) KClO2
c) KClO3
d) KClO4
Solution
18
Complete the following statements by selecting the correct option.
a) The formula of a compound represents
i) an atom
ii) a particle
iii) a molecule
iv) a combination
b) The correct formula of aluminium oxide is
i) AlO3
ii) AlO2
iii) Al2O3
iv) Al3O2
c) The valency of Nitrogen in Nitrogen dioxide (NO2) is
i) One
ii) Two
iii) Three
iv) Four
Solution
a) The formula of a compound represents
i) an atom
ii) a particle
iii) a molecule
iv) a combination
b) The correct formula of aluminium oxide is
i) AlO3
ii) AlO2
iii) Al2O3
iv) Al3O2
c) The valency of Nitrogen in Nitrogen dioxide (NO2) is
i) One
ii) Two
iii) Three
iv) Four
Solution
19
Give the names of the elements and number of atoms of those elements, present in the following compounds.
a) Sodium sulphate
b) Quick lime
c) Baking soda (NaHCO3)
d) Ammonia
e) Ammonium dichromate
Solution
a) Sodium sulphate
b) Quick lime
c) Baking soda (NaHCO3)
d) Ammonia
e) Ammonium dichromate
Solution
20
The formula of the sulphate of an element M is M2(SO4)3. Write the formula of it.
a) Chloride
b) Oxide
c) Phosphate
d) Acetate
Solution
a) Chloride
b) Oxide
c) Phosphate
d) Acetate
Solution