Question

hat is the role of long chimneys in factories?
II. State whether the statements given below are True or False:
1. We cannot see air.
2. Air is a compound and not an element.
3. A firki rotates only in an open area or in a closed room with the ceiling fan switched on.
4. Open areas allow air to move here and there:
5. Air is an opaque material.​

Answer 1

Answer:

1. True

2. True

3. False

4. True

5. False

Answer 2

Answer:

1.true

2. true

3.false

4.true

5.false

Explanation:

1.Air is transparent to our eyes because we have evolved retinas that are sensitive to the very wavelengths of light that pass through it unobstructed – otherwise we wouldn't be able to see anything at all.

2.Air is a mixture and not a compound because of the following reasons: Air can be separated into its constituents such as oxygen, nitrogen etc. by fractional distillation of liquid air. Air shows the properties of all the gases present in it.

3.Moving air is responsible for rotation of firki in an open area. This moving air or wind is absent in a closed area, that is why firki does not rotate in a closed area

4.Air is a compound and not an element. ' A firki rotates only in an open area or in a closed room with the ceiling fan switched on. Open areas allow air to move here and there

5.AMaterials like air, water, and clear glass are called transparent. When light encounters transparent materials, almost all of it passes directly through them. Glass, for example, istransparent to all visible light. Translucent objects allow some light to travel through them.