Chapter U4, Problem 8STP

Interpretation Introduction

Interpretation:

The correct description of a 500 mL bottle filled completely with water needs to be identified.

Concept introduction:

The density of a substance is related to mass and volume as follows:

$d=\frac{m}{V}$

Here, m is mass and V is volume.

Also, number of moles is related to mass and molar mass as follows:

$n=\frac{m}{M}$

Here, m is mass and M is molar mass.

Answer to Problem 8STP

The correct option is (A).

Explanation of Solution

In the given question, the total capacity of bottle is 500 mL and it is completely filled with water. Thus, volume of water is 500 mL. Now, density of water is 1 g/mL thus, mass of water will be 500 g.

Number of moles can be calculated from mass and molar mass as follows:

$\begin{array}{l}\text{mole = mass × molar mass}\\ \text{ 500g }\times \text{ 18 g /mol}\\ \text{ = 9000 mol}\end{array}$

So, the correct option is (A).