If the density of the solution is 3.12 g ml^-1, then what will be the mass of the 1.5 ml solution in two significant figures?

1.	\(4.4~\mathrm{g}\)	2.	\(4680 \times 10^{3} ~\mathrm{g}\)
3.	\(4.7~\mathrm{g}\)	4.	\(46.80~\mathrm{g}\)

Match the following physical quantities with units.

Codes:

An oxide of iron contains 69.9% iron and 30.1% oxygen by mass. What is its empirical formula?

1. FeO

2. Fe₂O₃

3. Fe₃O₄

4. Fe₃O₂

Percentage of C, H & N in 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. $C{H}_{3}N$

How many significant figures are present in the following numbers?

1. 3, 3, 3
2. 3, 4, 3
3. 3, 2, 3
4. 3, 4, 4

The mass of CaCO₃ required to react completely with 25 mL of 0.75 M HCl according to the given reaction would be:

\(CaCO_3 (s)\ + \ HCl (aq)\ \rightarrow CaCl_2(aq)\ + CO_2(g)\ \\~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~+ H_2O(l)\)
 

1. 0.36 g

2. 0.09 g

3. 0.96 g

4. 0.66 g

One mole of oxygen gas at STP is equal to:

Choose the correct answer from the option given below: 

Sulphuric acid reacts with sodium hydroxide according to the reaction:

${\mathrm{H}}_2{\mathrm{SO}}_4+2\mathrm{NaOH}\to {\mathrm{Na}}_2{\mathrm{SO}}_4+2{\mathrm{H}}_2\mathrm{O}$

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-

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