Question

a.
Calculate no. of moles of hydrogen molecules
present in 1.2 x 10^24 molecules of Hydrogen​

Answer 1

Solution: No. of molecules = No. of moles × Avogrado Number

→ 1.2 × 10²⁴ molecules = No. of moles × 6.022 × 10²³

→ 1.2 × 10²⁴/6.022 × 10²³ = No. of moles

→ 0.199 × 10 = No. of moles

→ 1.99 or 2 = Number of moles

There are 2 moles of hydrogen molecules in 1.2 × 10²⁴ molecules of hydrogen

Answer 2

★ GiveN :

Number of molecules = 1.2 $\times$ 10²⁴.

$\rule{200}{1}$

★ To FinD :

We have to find the number of moles present in the hydrogen molecules.

$\rule{200}{1}$

★ ExplanatioN :

We know the formula to find the number of molecules.

$\small{\star{\boxed{\sf{No. \: of \: molecules = No. \: of \: moles \times Avagadro \: Number}}}}$

★ Putting Values ★

$\sf{\dashrightarrow 1.2 \times 10^24 = No. \: of \: moles \times Avagadro \: Number}$

→ We know value of Avagadro number = 6.022 $\times$ 10²³

$\sf{\dashrightarrow 1.2 \times 10^{24} = No. \: of \: moles \times 6.022 \times 10^{24}} \\ \\ \sf{\dashrightarrow \dfrac{1.2 \times 10^{24}}{6.022 \times 10^{23}} = No. \: of \: moles} \\ \\ \sf{\dashrightarrow No. \: of \: Moles = 0.199 \times 10} \\ \\ \sf{\dashrightarrow No. \: of \: Moles = 1.99} \\ \\ \Large{\implies{\boxed{\boxed{\sf{No. \: of \: Moles = 1.99}}}}}$