# The number of significant figures in the following numbers is:   (I). 161 cm (II). 0.0161 (III). 1.61 1. 3, 3, 3 2. 3, 4, 3 3. 3, 2, 3 4. 3, 4, 4

Subtopic:  Introduction |
73%
From NCERT
AIPMT - 1998
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 mass of CaCO3 required to react completely with 25 mL of 0.75 M HCl according to the given reaction would be:

CaCO3(s) + HCl(aq) ➡ CaCl2(aq) + CO2(g) + H2O(l)

1. 0.36 g

2. 0.09 g

3. 0.96 g

4. 0.66 g

Subtopic:  Concentration Based Problem | Equation Based Problem |
62%
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

One mole of oxygen gas at STP is equal to:

 (a) 6 .022× 1023 molecules of oxygen (b) 6.022 × 1023 atoms of oxygen (c) 16 g of oxygen molecule (d) 32 g of oxygen

1. (a) and (b)

2. (a) and (c)

3. (a) and (d)

4. (c) and (d)

Subtopic:  Moles, Atoms & Electrons |
74%
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

Sulphuric acid reacts with sodium hydroxide as follows

${\mathrm{H}}_{2}{\mathrm{SO}}_{4}+2\mathrm{NaOH}\to {\mathrm{Na}}_{2}{\mathrm{SO}}_{4}+2{\mathrm{H}}_{2}\mathrm{O}$

When 1L of 0.1 M sulphuric acid solution is allowed to react with 1 L of 0.1 M sodium hydroxide solution, the amount of sodium sulphate formed and its molarity in the solution obtained are respectively-

1. 0.1 M, 7.10 g

2. 7.10 g, 0.025 M

3. 0.025 M, 3.55 g

4. 3.55 g, 0.25 M

Subtopic:  Concentration Based Problem |
54%
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 correct match is:
 List I List II a. Micro i. ${10}^{-15}$ m b. Mega ii. ${10}^{-6}$ m c. Giga iii. ${10}^{6}$ m d. Femto iv. ${10}^{9}$ m

 a b c d 1. i iv iii ii 2. iii iv ii i 3. ii iii iv i 4. i iii iv ii
Subtopic:  Introduction |
87%
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

Percentage of C, H & N of a compound is given as follows:
C=40%, H=13.33%, N=46.67%
The empirical formula of the compound will be:

1. $C{H}_{2}N$

2. ${C}_{2}{H}_{4}N$

3. $C{H}_{4}N$

4. $C{H}_{3}N$

Subtopic:  Empirical & Molecular Formula |
76%
From NCERT
AIPMT - 1998
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

When 50.0 kg of nitrogen gas (N2) and 10.0 kg of hydrogen gas (H2) are combined, what is the quantity of ammonia gas (NH3) produced?

1. 33.0 ×103 mol

2. 56.1×103 g

3. 6.5 ×103 g

4. None of the above

Subtopic:  Limiting Reagent |
58%
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 solution is prepared by adding 2 g of substance A to 18 g of water. The mass percent of the solute is-

1. 20%

2. 10%

3. 15%

4. 18%

Subtopic:  Concentration Based Problem |
87%
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 NaNO3 weighed out to make 50 mL of an aqueous solution containing 70.0 mg Na+ per ml is:

(Rounded off to the nearest integer) [Given: Atomic weight in g mol–1 – Na: 23; N: 14; O: 16]

1. 13 g

2. 26 g

3. 18 g

4. 22 g

Subtopic:  Concentration Based Problem |
60%
From NCERT
Hints

An aqueous solution of urea containing 18 g of urea in 1500 cm3 of the solution has a density of 1.052 g/cm3. If the molecular weight of urea is 60, then the molality of the solution is-
1. 0.2
2. 0.192
3. 0.064
4. 1.2

Subtopic:  Concentration Based Problem |
69%
From NCERT