Question

calculate nember of molecule present in 09 gm of h2o ​

Answer 1

Answer:

1. We know that 1 mole of any compound contains 6.022 x 1023 molecules of that compound.

2. Here, mass of water = 9 gm.

3. Molar mass of water (H2O) = (2 x 1 + 1 x 16)g/mol = 18g/mol.

4. ∵ 18 g (= 1 mol of H2O contains 6.02 x 1023 molecules.

Answer 2

Answer:

Number of molecules present in 9 g of $H_{2} O$ is  3.011 * $10^{23}$ molecules.

Explanation:

Given mass of $H_{2} O$ = 9 g

Molar mass of $H_{2} O$ = 2*(Molar mass of H) + Molar mass of O

                                = 2*(1.007) + 16

                                = 18.014 g/mol

Number of moles = given mass / molar mass

                             = $\frac{9}{18.014}$

                             = 0.499 ≈ 0.5 moles

1 mole $H_{2} O$ contains 6.022 * $10^{23}$ molecules

Therefore 0.5 moles of $H_{2} O$ contains 0.5 * 6.022 * $10^{23}$ molecules

= 3.011 * $10^{23}$ molecules.