Chapter 5 Chemistry

When soap is added into a beaker containing hard water, a white precipitate is formed. which of the following ion is responsible of the white precipitate ?

• Zn²⁺
• Pb²⁺
• Al³⁺
• Ca²⁺

Both soap and detergent are classified as

• salt
• ester
• alkane
• alkali

Which of the following is not an advantage of using detergent?

• Environmental friendly
• Only small amount is required
• Effective even when used in hard water
• Function change with the type of covalent structure

what is the main source in the production of detergent?

• palm oil

• animal fat

• ammonia

• petroleum

a group of scouts go camping by the seashore. they have to do all their washing using sea water.

what is the suitable substance for them to wash their clothes effectively?

• soap

• bleach

• detergent

• antiseptic

which of the following are used to make detergents?

• I and II

• II and III

• III and IV

• I and III

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-3

NGSS.MS-PS1-5

which cation present in hard water?

• Mg2+

• Zn2+

• Pb2+

• Sn2+

the effectiveness of cleansing action of soap is lower in hard water compared to in soft water.

which of the following explain the above statement?

• soap is less soluble in hard water

• soap dissociates partially in hard water

• soap forms insoluble salt with calcium and magnesium ions

• soap particles form complex ions with aluminium ion present in hard water

why sodium chloride used in preparation of soap?

• to speed up the reaction to produce soap

• to produce soap with foams easily

• to reduce the solubility of soap

• to make soap softer

name the process of soap preparation

• hydrolysis

• soapication

• sulphonation

• saponification