On washing with soap, a turmeric stain on the cloth turns to red because
A. soap solution is alkaline.
B. soap solution is acidic.
C. turmeric contains a natural indicator.
D. turmeric contains litmus.
Select the correct alternative.

Which of the following substances cause temporary hardness in water?

$1. Mg{\left(HC{O}_3\right)}_2$

$2. Ca{\left(HC{O}_3\right)}_2$

$3. CaC{l}_2$

$4. MgS{O}_4$

Select the correct answer using the code given below.

The instrument used to regulate temperature to a particular degree is called:

1. Thermostat

2. Thermometer

3. Pyrometer

4. Thermocouple

Human nails are made up of:

1. Pigment
2. Elastin
3. Albumin
4. Keratin

Which of the following is not a bleaching agent?

1. Sodium hypochlorite
2. Calcium hypochlorite
3. Hydrogen peroxide
4. Hydrogen sulphide

Pressure is measured terms of:

1. Mass and Density

2. Work Done

3. Force and Area

4. Force and Distance

Soap solution used for cleaning purpose appears cloudy. This is due to the fact that soap micelles can _____.