Question

Number of hydrogen atoms in 2g hydrogen gas at STP are ( )

A) 6.02x1023 B) 6.02x1024 C) 6.02x10-23 D) 6.02x1022​

Answer 1

Explanation:

6.022×10²³ is the correct answer

Answer 2

The given amount of hydrogen gas, at STP, contains Avogadro's number of atoms, that is, 6.022 x 10^23 atoms. (Option-A)

Given,

2 grams of Hydrogen gas.

To find,

The number of hydrogen atoms in given amount of hydrogen gas at STP.

Solution,

We can simply solve this numerical problem by using the following process:

As per stoichiometry;

1 mole of any gas at STP contains Avogadro's number of atoms, that is, 6.022 x 10^23 atoms.

{Statement-1}

Now, each hydrogen gas molecule (H2) contains 2 hydrogen atoms each.

=> Molar mass of hydrogen gas = 2×(atomic mass of hydrogen) = 2×(1 g) = 2 g

{statement-2}

Now, according to statement-2, the number of moles equivalent of 2g hydrogen gas = 1 mole

Now, according to statement-1;

1 mole of hydrogen gas, that is, the given amount of hydrogen gas, at STP, contains Avogadro's number of atoms, that is, 6.022 x 10^23 atoms.

Hence, the given amount of hydrogen gas, at STP, contains Avogadro's number of atoms, that is, 6.022 x 10^23 atoms. (Option-A)