Density of water at room temperature is 1 g/ml. How many molecules are there in a drop of water, if its volume is 0.05 ml?

Question

Density of water at room temperature is 1 g/ml. How many molecules are there in a drop of water, if its volume is 0.05 ml? (A) 1.67 × 1021 (B) 16.7 × 1021 (C) 6.023 × 1023 (D) 1.67 × 1023

Tardigrade Admin · Accepted Answer

Density of water at room temperature = 1 g/mol ∴ 1 ml contain (1/18) moles of H2O 0.05 ml will contain 0.05 × (1/18) moles ∴ 1 mole = 6.022 × 1023 moles Total number of molecules in a drop of water = 6.023 × 1023 × 0.05 × (1/18) = 1.67× 1021

Q. Density of water at room temperature is $1 g / m l$ . How many molecules are there in a drop of water, if its volume is $0.05 m l$ ?

$1.67 \times 1 0^{21}$

$16.7 \times 1 0^{21}$

$6.023 \times 1 0^{23}$

$1.67 \times 1 0^{23}$

Q. Density of water at room temperature is 1g/ml. How many molecules are there in a drop of water, if its volume is 0.05ml?

1.67×1021

16.7×1021

6.023×1023

1.67×1023

Density of water at room temperature =1g/mol ∴1ml contain 181​ moles of H2​O 0.05ml will contain 0.05×181​ moles ∴1 mole =6.022×1023 moles Total number of molecules in a drop of water =6.023×1023×0.05×181​ =1.67×1021

Q. Density of water at room temperature is $1 g / m l$ . How many molecules are there in a drop of water, if its volume is $0.05 m l$ ?

$1.67 \times 1 0^{21}$

$16.7 \times 1 0^{21}$

$6.023 \times 1 0^{23}$

$1.67 \times 1 0^{23}$