# The number of moles of hydrogen atoms present in 3 moles of ethane (C2H6), will be- 1. 18.069 × 1023 2. 1.8 × 1023 3. 18 4. 6 × 1023

Subtopic:  Moles, Atoms & Electrons |
65%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

20 g of sugar is dissolved in enough water to make a final volume of 2L. The concentration of sugar (C12H22O11) in mol L–1  will be:

1. 0.29 mol/L

2. 0.029 mol/L

3. 0.35 mol/L

4. 0.032 mol/L

Subtopic:  Concentration Based Problem |
77%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

If the density of methanol is 0.793 kg L–1, the volume needed for making 2.5 L of its 0.25 M solution would be:

1. 22.25 mL

2. 24.78 mL

3. 25.22 mL

4. 22.52 mL

Subtopic:  Concentration Based Problem |
60%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

If the mass of air at sea level is 1034 g cm–2, pressure in pascal will be:

1. 1.01332 × 105 Pa

2. 1.01332 × 106 Pa

3. 1.01332 × 10Pa

4. 1.01332 × 108 Pa

Subtopic:  Introduction |
67%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The SI unit of mass is:

1. Kilogram (kg)

2. Gram (g)

3. Pascal (Pa)

4. Kilometres (km)

Subtopic:  Introduction |
88%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A significant figure is defined as :

 1 The total number of digits in a number, including the last digit that represents the uncertainty of the result. 2 The total number of digits in a number, excluding the last digit, which represents the uncertainty of the result. 3 The total number of digits in a number including the last digit that represents the certainty of the result. 4 The total number of last digits that represents the uncertainty of the result.

Subtopic:  Introduction |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The chloroform contamination level in water is 15 ppm (by mass of chloroform). The molality of chloroform in the water sample would be:

1. 3.25 × 10-4

2. 1.5 × 10-3

3.  7.5 × 10-3

4. 1.25 × 10-4

Subtopic:  Concentration Based Problem |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

If the speed of light is 3.0 × 108 m s–1, then the distance covered by light in 2.00 nanoseconds will be -

1. 0.500 m

2. 0.600 m

3. 0.700 m

4. 0.800 m

Subtopic:  Introduction |
89%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

In a reaction A + B2 → AB2,
A will act as a limiting reagent if :

 i. 300 atoms of A reacts with 200 molecules of B ii. 2 moles A reacts with 3 moles B2 iii. 100 atoms of A reacts with 100 molecules of B iv. 5 moles A reacts with 2.5 moles B v. 2.5 moles A reacts with 5 moles B2

Choose the correct option:

1. (i), (ii)
2. (i), (ii), (v)
3. (ii), (v)
4. All

Subtopic:  Limiting Reagent |
70%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

If 10 volumes of H2 gas react with 5 volumes of O2 gas, the volumes of water vapor produced would be:

1. 9

2. 8

3. 10

4. 11

Subtopic:  Equation Based Problem |
88%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch