Some basic concepts of chemistry practice · Easy

If a mixture containing 3 moles of hydrogen and 1 mole of nitrogen is converted completely into ammonia, the ratio of initial and final volumes under the same temperature and pressure would be:

How many g are present in one mole of Ag?

$2.24 {~L}$ of ${CH}_4$ at NTP contains :-

Equivalent weight of a bivalent metal is 37.2. The molecular weight of its chloride is

Molar concentration of a solution in water is:

Assertion: Atomicity of phosphorus is four.
Reason: Atomicity is the number of atoms present in 1 molecule.

The number of atoms in 4.25 g of $N{H_3}$ is

The ratio of the masses of methane and ethane in a gas mixture is $4: 5$. The ratio of number of their molecules in the mixture is

Give the correct order of initials T or F for following statements. Use T if statement is true and F if it is false.
(i) Gay-Lussac’s law of gaseous volumes is actually the law of definite proportion by volume.
(ii) Law of conservation of mass is true for physical change, but not for chemical change.
(iii) The percentage of oxygen in $H_2O_2$ is different from that in $H_2O.$ Hence, it violates law of definite proportions.
(iv) Fixed mass of A reacts with two different masses of B (say x and y), then the ratio of x/y can be any positive integer.
(v) At STP, 5 mL of $N_2$ and $H_2$ have different no. of molecules.

A: Number of ions in 9 gram of ${NH}_4^{+}$is equal to Avogadro's number $\left({N}_{{A}}\right)$.

R: Number of ions is equal to number of atoms.

Equivalent weight of $\mathrm{FeS}_2$ in the half reaction, $\mathrm{FeS}_2 \longrightarrow \mathrm{Fe}_2 \mathrm{O}_3+\mathrm{SO}_2$ is :

Insulin contains 3.4% Sulphur. The minimum mol. weight of insulin is:

Which one of the following is not a redox reaction

Dulong and Petit’s law is valid only for

One mole of molecules of dioxygen represents

Which property of an element is not variable?

The mole fraction of solute in one molal aqueous solution is:

40 milligram diatomic volatile substance $\left(X_2\right)$ is converted to vapour that displaced $4.92 \mathrm{~mL}$ of air at $1 \mathrm{~atm}$ and $300 \mathrm{~K}$. Atomic weight of element $X$ is nearly:

Max. no. of gram molecules are present in:

Moon takes 27.3 days to complete one orbit around the Earth. Now read the following statements and choose the correct code. Here T is for true statement and F is for ‘False statement’.
(i) Moon takes 655.2 hours to complete one orbit around the Earth.
(ii) Moon takes 39312 seconds to complete one orbit around the earth.
(iii) Moon takes 1638 minutes to complete one orbit around the Earth.

One mole of ${\mathrm{P}_4}$ molecules contain:

Maximum number of atoms is present in

If the true value for an experimental result is 6.23 and the results reported by three students X, Y and Z are :

X : 6.18 and 6.28

Y : 6.20 and 6.023

Z : 6.22 and 6.24

Which of the following option is correct :

Assertion: Density $=$ specific gravity $\times 0.99823$ at $20^{\circ} \mathrm{C}$.
Reason: Density $=$ specific gravity at $4^{\circ} \mathrm{C}$.

2.79 g of silver carbonate on being strongly heated yields a residue weighing:

The hardness of water is usually expressed in:

Mole fraction of solvent in $10 \%\left(\frac{w}{w}\right)$ aqueous $\mathrm{NaOH}$ is

Which has the maximum number of molecules among the following

In 4 moles of ethane, the number of molecules of ethane are

24 g of metal react with an acid and liberated 22.4 litres of hydrogen at STP. The equivalent wt of the metal is