# Lakhmir Singh & Manjit Kaur Test: Atoms and Molecules

## 15 Questions MCQ Test General Science(Prelims) by IRS Divey Sethi | Lakhmir Singh & Manjit Kaur Test: Atoms and Molecules

Description
Attempt Lakhmir Singh & Manjit Kaur Test: Atoms and Molecules | 15 questions in 15 minutes | Mock test for Class 9 preparation | Free important questions MCQ to study General Science(Prelims) by IRS Divey Sethi for Class 9 Exam | Download free PDF with solutions
QUESTION: 1

### Argentum is the Latin name of

Solution:

The Latin name of Silver is Argentum. The symbol of Silver is Ag.

QUESTION: 2

Solution:
QUESTION: 3

### What is the name given to 6.022 × 1023?

Solution:

Fixed number of atoms or molecules present in gram atomic mass of an atom or molecules is 6.022 × 1023.Thisnumber is known as Avogadro constant.

QUESTION: 4

Match the following with correct response. Solution:
QUESTION: 5

The number of moles for 52g of He is:
(Atomic Mass of He: 4u)

Solution:

Gram atomic mass of He = 4u
Therefore 52 g of He contains :
= 52 / 4
= 13 moles

QUESTION: 6

Which of the following is anion?
A. Magnesium
B. Sulphate
C. Oxalate
D. Ammonium

Solution:

C is the correct option.a negatively charged ion, i.e. one that would be attracted to the anode in electrolysis.
A. Magnesium (+2)
B. Sulphate (-2)
C. Oxalate (-2)
D. Ammonium(+1)
Hence, only B and C are Anions.

QUESTION: 7

Calculate the number of particles in 0.01 mole of carbon atoms

Solution:

One mole of carbon contains6.022 × 1023atoms of carbon. The number of particles present in 0.01 mole of carbon = 6.022 × 1023×0.01=6.022 × 1021atoms.

QUESTION: 8

Match the following with correct response. Solution:
QUESTION: 9

Phosphorus is a

Solution:

Phosphorus is tetra-atomic. Each molecules of phosphorus contain 4 atoms.

QUESTION: 10

What is the ratio of magnesium and Sulphur by mass in Magnesium sulphide?

Solution:

Atomic mass of Magnesium is 12 and Sulphur is 16. Therefore, the ratio of Magnesium ans Sulphur by mass is 12:16 = 12/16 = 3:4.

QUESTION: 11

A sample of CaCO3 conatins 3.01×1023 ions of Ca2+ and (CO3)2-.The mass of the sample is

Solution:

The mass of one mole of CaCO3 is equal to 100 g. one mole of is equal to 6.022 × 1023ions. Therefore, mass of 3.01×1023 ions = 50 g

QUESTION: 12

Which is not true about H2SO4?
A. It is composed of 2 Hydrogen, 1 Sulpher and 4 Oxygen atoms
B. It relative molecular mass is 98
C. It is composed of one molecule of H2 One atom S and two molecules O2
D. Its relative molecular mass is 108

Solution:

98.07848 g mol

The formula for sulfuric acid is H2SO4. The molar mass of sulfuric acid is 98.07848 g mol.

QUESTION: 13

How many times an atom Sulphur is heavier than an atom of carbon?

Solution:

Atomic mass of Sulphur is 32 u and atomic mass of Carbon is 12 u. So, mass of Sulphur is 32/12 times heavier than Oxygen. = 8/3 times.

QUESTION: 14

“Gram atomic mass of an element and the gram molecular mass of a compound contains the same number of molecules” is a

Solution:

Gram atomic mass of an element and the gram molecular mass of a compound contain the same number of molecules, which is equal to6.022×1023molecules.

QUESTION: 15

Which of the following is correct definition of a mole?
A. It is equal to the gram atomic mass of the substance
B. It contain 6.022×1020 atoms of a given substance
C. It is equal to gram molecular mass of the substance
D. It contain 6.022×1023 molecules of a given substance

Solution: Use Code STAYHOME200 and get INR 200 additional OFF Use Coupon Code