Which of the following is not correctly matched ?
Element
Symbol
(A) Antimony
Sb
(B) Tin
Ti
(C) Tungsten
W
(D) Rhenium
Re
Important Questions on General Science
Water is a compound because:
(A) It exists as solid, liquid, or gas.
(B) It contains hydrogen and oxygen.
(C) It has two different elements joined by chemical bonds.
(D) It cannot be split up into simpler substances by chemical means.
Potassium permanganate is used for purifying drinking water because:
(A) It dissolves the impurities of water
(B) It is a sterilizing agent
(C) It is an oxidizing agent
(D) It reduces agent
When an iron nail gets rusted, iron oxide is formed:
(A) Without any change in the weight of the nail
(B) With increase in the weight of the nail
(C) With decrease in the weight of the nail
(D) Without any change in colour or weight of the nail
Match the following-
| Elements | Nature of elements |
| (a) Sodium | 1. Gas |
| (b) Phosphorus | 2. Halogen |
| (c) Iodine | 3. Alkali metal |
| (d) Radon | 4. Transition metal |
| 5. Non-metal |
codes:
| (a) | (b) | (c) | (d) | |
| (A) | 2 | 5 | 3 | 1 |
| (B) | 3 | 5 | 2 | 1 |
| (C) | 4 | 2 | 3 | 5 |
| (D) | 5 | 3 | 4 | 2 |
The hardest substance available on the earth is--
(A) Platinum
(B) Coal
(C) Diamond
(D) Gold
Actinides are the elements with atomic numbers from-
(A) 36 to 43
(B) 89 to 103
(C) 97 to 114
(D) 101 to 115
Which of the following pairs is not correctly matched?
| Mineral | Industrial use |
| (A) Zircon | Nuclear reactors |
| (B) Manganese ore | Dry battery |
| (C) Mica |
Bleaching powder |
| (D) Bauxite | Tanning |
The average salinity of sea water is-
(A) 20%
(B) 25%
(C) 30%
(D) 35%
