classification of elements, chemical bonding, periodicity in properties & physical transformation - Category wise Question and Answer Practice Test with Solutions

Question : 1

Consider the following statements regarding Bohr atomic model:

1. It introduces the idea of stationary orbits.
2. It assumes that the angular momentum of the electron is equal to -$(1/2)h/{2π}$
3. It uses the planetary model of the atom involving circular orbits.

a) 1 and 3

b) 1 and 2

c) 2 and 3

d) 1, 2 and 3

Question : 2

Which of the following are values of gas constant R ?

1. 0.0821 L atm k^–1mol^–1
2. 8.21 L torr k^–1mol^–1
3. 82.1 atm mL k^–1mol^–1
4. 8.314 J mol^–1k^–1

a) 1, 2 and 4

b) 1, 2 and 3

c) 1, 3 and 4

d) 2, 3 and 4

Question : 3

Element A belongs to Group VII in p-block and element B belongs to Group I in s-block of the periodic table. Out of the following assumptions, the correct one is :

a) A and B are non-metals

b) A is a metal and B is a non-metal

c) A and B are metals

d) A is a non-metal and B is a metal

Question : 4 [UPPCS (Pre) 1994]

Why does water boil at a temperature below 100ºC at higher altitudes?

a) The gravitational attraction is less

b) Because of heavy winds in mountains

c) The atmospheric pressure decreases and hence boiling point is lowered

d) None of the above is correct

Question : 5 [IAS (Pre) 2014]

Which of the following is/are the example/examples of chemical change?

1. Crystallization of sodium chloride
2. Melting of ice
3. Souring of milk

a) Only 3

b) 1, 2 and 3

c) Only 1 and 2

d) None of the above