All Chemistry MCQs

Question 1

Sodium (Na = 23) crystallizes in a bcc arrangement with the interfacial separation between the atoms at the edge 53.6pm. The density of sodium crystal is:

Accepted Answer

None of these

Answer

2.07 g/cc

Answer

2.46 g/cc

Answer

1.19 g/cc

Question 2

An atomic solid has a hexagonal arrangement of unit cells with a height of the hexagonal (in close close-packed arrangement) as "h". The radius of an atom in terms of height is:

Accepted Answer

r=3h/4

Answer

r=h/3.266h

Answer

r=h/2

Answer

r=h/1.633

Question 3

A compound formed by elements A and B has a cubic structure in which A atoms are at the corners of the cube and B atoms are at the face centres. The formula of the compound will be:

Accepted Answer

AB3

Answer

A4B3

Answer

A2B

Answer

A2B3

Question 4

NH4Cl crystallizes in a body-centred cubic lattice with an edge length of the unit cell equal to 387 pm. If the radius of the Cl− ion is 181 pm, the radius of the NH4+ ion is:

Accepted Answer

154.1 pm

Answer

92.6 pm

Answer

366.3 pm

Answer

None of these

Question 5

A substance has a density of 2 kg dm-3 and it crystallizes in a fcc lattice with an edge length equal to 700 pm, then the molar mass of the substance is:

Accepted Answer

103.30 g mol-1

Answer

74.50 g mol-1

Answer

56.02 g mol-1

Answer

65.36 g mol-1

Question 6

Find the Error.The United States is(A) anxious to(B) improve their(C) image in Latin America(D).

Accepted Answer

their

Answer

The United States is

Answer

anxious to

Answer

in Latin America

Question 7

Select the most suitable synonym for the given word:COLLIDED WITH

Accepted Answer

Struck

Answer

Rebuff

Answer

Stop

Answer

Harmonise

Question 8

Spot the error. The pines onto top of the mountain above us looked as if the fingers of their long boughs were fondling the substance of a white cloud.

Accepted Answer

onto

Answer

above

Answer

as if

Answer

were

Question 9

Statement: Every year, at the beginning or at the end of the monsoons, we have some cases of conjunctivitis, but this year, it seems to be a major epidemic, witnessed after nearly four years.Courses of Action:I. Precautionary measures should be taken after every four years to check this epidemic.II. People should be advised to drink boiled water during rainy season.

Accepted Answer

Neither I nor II follows

Answer

Only I follows

Answer

Only II follows

Answer

Either I or II follows

Answer

Both I and II follow

Question 10

Statements: It is almost impossible to survive and prosper in this world without sacrificing ethics and morality.Conclusions:I. World appreciates some concepts but may not uphold it.II. Concept of ethics and morality are not practicable in life.

Accepted Answer

Only conclusion I follows.

Answer

Only conclusion II follows.

Answer

Either I or II follows.

Answer

Neither I nor II follows.

Answer

Both I and II follow.

Question 11

The following equation becomes mathematically correct when you interchange either the sign or the numbers as indicated in the question. Find the correct alternative. Given equation:(16 - 4) x 6 ÷ 2 + 8 = 30

Accepted Answer

÷ and -

Answer

4 and 2

Answer

16 and 6

Answer

- and +

Question 12

Statements: I. The government has allowed private airline companies in Pakistan to operate to overseas destinations. II. The national air carrier has increased its flights to overseas destinations.

Accepted Answer

Both the statements I and II are independent causes

Answer

Statement I is the cause and statement II is its effect

Answer

Statement II is the cause and statement I is its effect

Answer

Both the statements I and II are independent effects

Question 13

The osmotic pressure of equimolar solutions of BaCl2, NaCl and sucrose will be in the order:

Accepted Answer

BaCl2 > NaCl > Sucrose

Answer

Sucrose > NaCl > BaCl2

Answer

Sucrose > BaCl2 > NaCl

Answer

NaCl > BaCl2 > Sucrose

Question 14

Consider NaCl produced in the equation: FeCl3+ NaOH → Fe(OH)3 + NaCl 175.5g of NaCl was dissolved in water to make a liter of solution, the molarity would be:

Accepted Answer

3 M

Answer

0.1 M

Answer

8 M

Answer

12 M

Answer

16 M

Question 15

An azeotropic mixture of two liquids has a boiling point higher than either of them when it:

Accepted Answer

Shows negative deviation from Raoult's law

Answer

Shows positive deviation from Raoult's law

Answer

Shows ideal behaviour

Answer

Is saturated

Question 16

The number of moles of solute dissolved per liter of solution is called:

Accepted Answer

Molarity

Answer

Normality

Answer

Molality

Answer

Mole fraction

Answer

Percentage composition

Question 17

From a mixture of CO2 and H2 gases, CO2 can be separated by passing the mixture through:

Accepted Answer

Water under high pressure

Answer

Water at high temperature

Answer

Cold water

Answer

Acidified water

Question 18

The solubility product for BaSO4, at 18-25°C is:

Accepted Answer

1.0 x 10^-10 mol2dm-6

Answer

8.7 x 10^-36 mol2dm-6

Answer

1.8 x 10^-21 mol2dm-6

Answer

8.4 x 10^-28 mol2dm-6

Answer

3.5 x 10^-52 mol2dm-6

Question 19

0.5 molar solution NaOH contains:

Accepted Answer

20g NaOH in one dm3

Answer

40g NaOH in one dm3

Answer

80g NaOH in one dm3

Answer

10g NaOH in one dm3

Question 20

The temperature at which one crystalline form changes to other is called _ temperature:

Accepted Answer

Transition

Answer

Critical

Answer

Absolute

Answer

None of these

All Free Chemistry MCQs with Answers