Elements and Metals

Which of the following is an element?

A. Ruby

B. Sapphire

C. Emerald

D. Diamond

Potassium Permanganate is used for purifying drinking water, because

A. it is a sterilising agent

B. it dissolves the impurities of water

C. it is a reducing agent

D. it is an oxidising agent

Which of the following is the lightest metal?

A. Mercury

B. Lithium

C. Lead

D. Silver

Which of the following metals remain in liquid for under normal conditions?

A. Radium

B. Zinc

C. Uranium

D. Mercury

Actinides are the elements with atomic numbers from

A. 97 to 104

B. 101 to 115

C. 89 to 103

D. 36 from 43

The two elements that are frequently used for making transistors are

A. boron and aluminium

B. silicon and germanium

C. iridium and tungsten

D. niobium and columbium

The filament of an electric bulb is made of

A. tungsten

B. nichrome

C. graphite

D. iron

Diamond is an allotropic form of

A. germanium

B. carbon

C. silicon

D. sulphur

In fireworks, the green flame is produced because of

A. sodium

B. barium

C. mercury

D. potassium

Permanent hardness of water can be removed by adding

A. chlorine

B. washing soda

C. potassium permanganate

D. bleaching powder

English GK