4.4 g of an unknown gas occupies 2.24 litres of volume at NTP. The gas may be [MP PMT 1995]

(1) Carbon dioxide

(2) Carbon monoxide

(3) Oxygen

(4) Sulphur dioxide

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

The mass of carbon present in 0.5 mole of K4[Fe(CN)6] is:

1. 1.8 g 2. 18 g
3. 3.6 g 4. 36 g
Subtopic:  Moles, Atoms & Electrons |
 73%
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 number of moles of oxygen in one litre of air containing 21% oxygen by volume under standard conditions is [CBSE PMT 1995]

(1) 0.186 mole

(2) 0.21 mole

(3) 0.0093 mole

(4) 2.10 mole

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

advertisementadvertisement

The empirical formula of an organic compound containing carbon and hydrogen is CH2. The mass of one litre of this organic gas is exactly equal to that of one litre of N2. Therefore, the molecular formula of the organic gas is:

1. \(\mathrm{C}_2 \mathrm{H}_4\) 2. \(\mathrm{C}_3 \mathrm{H}_6\)
3. \(\mathrm{C}_6 \mathrm{H}_{12}\) 4. \(\mathrm{C}_4 \mathrm{H}_8\)

Subtopic:  Moles, Atoms & Electrons | Empirical & Molecular Formula |
 80%
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

An organic compound containing C, H and N gave the following on analysis: C = 40%, H = 13.3% and N = 46.67%. It's empirical formula would be [CBSE PMT 1999, 2002]

(1) CHN

(2) C2H2N

(3) CH4N

(4) C2H7N

Subtopic:  Empirical & Molecular Formula |
 82%
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 volume of oxygen at STP required to completely burn 30 ml of acetylene at STP is [Orissa JEE 1997]

(1) 100 ml

(2) 75 ml

(3) 50 ml

(4) 25 ml

Subtopic:  Equation Based Problem |
 80%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints

advertisementadvertisement

If Avogadro number NA, is changed from 6.022 x 1023 mol-1 to 6.022 x 1020 mol-1 this would change

(1) the definition of mass in units of grams

(2) the mass of one mole of carbon

(3) the ratio of chemical species to each other in a balanced equation

(4) the ratio of elements to each other in a compound

Subtopic:  Moles, Atoms & Electrons |
 76%
From NCERT
NEET - 2015
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints

6.02 x 1020 molecules of urea are present in 100 mL of its solution. The concentration of the solution is

(a) 0.02 M

(b) 0.01 M

(c) 0.001 M

(d) 0.1 M

Subtopic:  Concentration Based Problem |
 82%
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints

A mixture of methane and ethene in the molar ratio of x : y has a mean molar mass of 20. What would be the mean molar mass. if the gases are mixed in the molar ratio of y : x?

(1) 22                               

(2) 24

(3) 20.8                           

(4) 19

Subtopic:  Moles, Atoms & Electrons |
 60%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints

advertisementadvertisement

The volume of a drop of water is 0.0018 mL then the number of water molecules present in two drop of water at room temperature is:

1.  12.046×1019

2.  1.084×1018

3.  4.84×1017

4.  6.023×1023

Subtopic:  Moles, Atoms & Electrons |
 51%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints