Chapter 9, Problem 15STP

Summary Introduction

To describe:

The kind of mixture formed when ink, pebbles and table salt are mixed with water.

Introduction:

A mixture is a combination of two or more substances in which each substance retains its individual characteristics and properties. There are two kinds of mixtures; homogenous mixture and heterogenous mixture. When a mixture has uniform composition throughout, it is called a homogenous mixture. In a heterogenous mixture, the components are distinct.

Answer to Problem 15STP

1. Ink will form a colloid with water.
2. Pebbles will form a heterogenous mixture with water.
3. Table salt will form a homogenous mixture with water.

Explanation of Solution

1. Ink + water- When ink is added to water, the particles remain suspended in water. They do not settle down even after some time. Such heterogenous mixtures are called colloids.
2. Pebbles + water-Pebbles do not dissolve in water. Instead, they settle down at the bottom of the container. Hence pebbles form a heterogenous mixture with water as the components are distinct.
3. Table salt + water- When table salt is added to water, it dissolves completely in water. Here water is a solvent and table salt is a solute. Together they form a salt solution in which the solute dissolves completely in solvent. A solution is a homogenous mixture. Hence table salt forms a homogenous mixture with water.