JAMB Chemistry Past Questions & Answers - Page 33

161.

Which one of the following is not a mixture?

A.

Air

B.

Mercury

C.

Milk

D.

Cement

Correct answer is B

A  mixture is a material made up of two or more different chemical substances which are not chemically combined. 

Mercury is a chemical element with the symbol Hg and atomic number 80.

162.

A 'breath test' used by traffic police to check drunken driving uses?

A.

Tumeric on filter paper

B.

Silica gel coated with saliva nitrate

C.

Potassium permanganate-sulphuric acid

D.

Potassium dichromatic-sulphuric acid

Correct answer is D

The earliest developed breathalyzer was based on reaction of alcohol if present in the exhaled air with a cocktail of chemicals containing sulfuric acid, potassium dichromate, silver nitrate, and water. Silver nitrate catalyzes the reaction between alcohol and potassium dichromate in acidic medium.

163.

What is the chemical name for the compound CuCO\(_{3}\)?

A.

Copper (iii) carbonate

B.

Copper (ii) carbonate

C.

Copper (i) carbonate

D.

Copper

Correct answer is B

Copper(II) carbonate or cupric carbonate is a chemical compound with formula CuCO\(_{3}\) 

164.

What is the IUPAC name for the following compound? HC\(\equiv\)CCH\(_{3}\)

A.

Acetylene

B.

Methyl acetylene

C.

Butanol

D.

Decanoic acid

Correct answer is B

Propyne (methylacetylene) is an alkyne with the chemical formula HC\(\equiv\)CCH\(_{3}\)

165.

The scientist who stated that matter can be converted into energy is? 

A.

Boyle

B.

Lavoiser

C.

Avogadro

D.

Einstein

Correct answer is D

The principle described by the physicist Albert Einstein's famous formula: E = mc^2, involves mass–energy equivalence.

I.e. the relationship between mass and energy.