Chemistry - Study Mode

[#421] The most abundant element in the human body is
Correct Answer

(D) Oxygen

Explanation

Solution: The most abundant element in the human body is oxygen.

[#422] The most abundant element in the earth’s atmosphere is
Correct Answer

(B) Nitrogen

Explanation

Solution: Nitrogen is a fairly inert gas at room temperature and is the most abundant element in Earth's atmosphere.

[#423] Select the one which is not a mixture :
Correct Answer

(D) Distilled water

Explanation

Solution: Water (H 2 O) is the most abundant compound on Earth's surface. Water is a compound because it contains oxygen and hydrogen which are chemically combined in proportion.

[#424] Which acid is used in Lead storage battery?
Correct Answer

(A) Sulphuric acid

Explanation

Solution: Lead storage battery uses sulphuric acid.

[#425] The acid used in lead storage cells is
Correct Answer

(D) Sulphuric acid
(H) Sulphuric acid

Explanation

Solution: Dilute sulfuric acid {H 2 SO 4 } serves as the electrolyte in a lead storage battery. The electrodes of the cells in a lead storage battery consist of lead grids. The openings of the anodic grid is filled with spongy (porous) lead. The openings of the cathodic grid is filled with lead dioxide {PbO 2 }.