Atoms and Molecules Test

Result

Atoms and Molecules Test - 10

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

How many moles are present in 40 g of He?

A
13 moles

B
10 moles

C
12 moles

D
14 moles

Solution

Number of moles of Helium = Mass of Helium / Molar mass of Helium = 40 / 4 = 10 moles. Atomic mass or molar mass of Helium is 4 u.
Question 2
1 / -0

Which of the following elements are present in Quick lime?

A
Sodium, Hydrogen, Oxygen

B
Calcium, Bromine

C
Calcium chloride

D
Calcium, Oxygen

Solution

The chemical formula of Quick lime is CaO. So, Calcium (Ca) and Oxygen (O) elements are present in Quick lime.
Question 3
1 / -0

What is the formula of calcium phosphide?

A
Ca₃(PO₄)₂

B
Ca₃P₂

C
CaCl₂

D
CaP

Solution

The valency of Calcium is 2 (Ca²⁺)and the valency of the Phosphide ion is 3 (P^3-). A chemical compound is always electrically neutral; so the positive and negative valencies of the ions or radicals present in calcium phosphide should add up to zero. Therefore, the chemical formula of calcium phosphide is Ca₃P₂
Question 4
1 / -0

What is the mass of 0.5 mole of Hydrogen atom ?

A
1 g

B
1.5 g

C
2.0 g

D
0.5 g

Solution

Atomic mass of hydrogen is 1 u. Mass of one mole of Hydrogen is equal to 1 g. Therefore, mass of 0.5 mole of Hydrogen atom will be 0.5 × 1 = 0.5g
Question 5
1 / -0

How many moles are present in 2.3 g of Na ?

A
0.1 mole

B
1 mole

C
2 mole

D
2/3 mole

Solution

Molecular mass of Sodium is 23 u. So, 23 g of Sodium (Na) is equal to 1 mole of Na.

Number of moles of Na present in 2.3 g of Na = Given mass of Na / Molar mass of Na = 2.3 / 23 = 0.1 mole
Question 6
1 / -0

What is the name given to 6.022 × 10²³?

A
Atomic mass

B
Mass number

C
Avogadro constant

D
None of these

Solution

Fixed number of atoms or molecules present in gram atomic mass of an atom or molecules is 6.022 × 10²³.This number is known as Avogadro constant.
Question 7
1 / -0

Calculate the number of particles in 0.01 mole of carbon atoms.

A
3.011 × 10²³ atoms

B
6.022 × 10²¹ atoms

C
12.033 × 10²³atoms

D
None of these

Solution

The number of particles in one mole of carbon atom = 6.022 × 10²³atoms

Therefore, the number of particles present in 0.01 mole of carbon = 6.022 × 10²³ × 0.01 = 6.022 × 10²¹atoms

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Atoms and Molecules Test - 10

Result

Atoms and Molecules Test - 10

Score

-

Rank

-

SHARING IS CARING

Question 1

13 moles

10 moles

12 moles

14 moles

Solution

Question 2

Sodium, Hydrogen, Oxygen

Calcium, Bromine

Calcium chloride

Calcium, Oxygen

Solution

Question 3

Ca3(PO4)2

Ca3P2

CaCl2

CaP

Solution

Question 4

1 g

1.5 g

2.0 g

0.5 g

Solution

Question 5

0.1 mole

1 mole

2 mole

2/3 mole

Solution

Question 6

Atomic mass

Mass number

Avogadro constant

None of these

Solution

Question 7

3.011 × 1023 atoms

6.022 × 1021 atoms

12.033 × 1023 atoms

None of these

Solution

User

Question Analysis

My Perfomance

Score

-

Rank

-

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.

Ca₃(PO₄)₂

Ca₃P₂

CaCl₂

3.011 × 10²³ atoms

6.022 × 10²¹ atoms

12.033 × 10²³atoms