The mass per unit volume of a substance is called density. (density =mass/volume). Arrange the following in order of increasing density-air, exhaust. From chimneys, honey, wter,chalk,cotton and iron.

Explanation

To arrange the substances in order of increasing density, we first need to understand the general trend of density among solids, liquids, and gases. Here’s a step-by-step solution:

### Step 1: Identify the substances and their states
We have the following substances to consider:
- Air (gas)
- Exhaust from chimneys (gas with impurities)
- Honey (liquid)
- Water (liquid)
...