Chemistry questions and answers

Chemistry Questions and Answers

Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.

936.

The relationship between the velocity (U) of gas molecules and their relative molecular mass (M) is shown by the equation

A.

U = (kM)\(\frac{1}{2}\)

B.

U = (kM)2

C.

U = \(\sqrt{\frac{k}{m}}\)

D.

U = \(\frac{k}{m}\)

Correct answer is C

The relationship between (U) of a gas molecule and the relative molecular mass is \(\bar{U}\) = (\(\frac{k}{m}\))\(^{\frac{1}{2}}\)

or \(\bar{U}\) = \(\sqrt{\frac{k}{m}}\)

937.

How much of magnesium is required to react with 260cm3 of 0.5 M HCl? [Mg = 24]

A.

0.3g

B.

1.5g

C.

2.4g

D.

3.0g

Correct answer is B

No explanation has been provided for this answer.

938.

The number of atoms of chlorine present in 5.85g of NaCl is [Avogaro's Number = 6.02 x 1023]

A.

6.02 x 1022

B.

5.85 x 1023

C.

6.02 x 1023

D.

5.85 x 1024

Correct answer is A

The number of atoms of chloride present in 5.85g of NaCl is 5.85 x 6.0 x 1023

= 6.02 x 1022

939.

10cm3 of hydrogen fluoride gas react with 5cm3 of dinitrogen difluoride gas (N2F2) to form 103 of a single gas. Which of the following is the most likely equation of the reaction?

A.

HF + N2F2 \(\to\) N2HF3

B.

2HF + N2F2 \(\to\) 2NHF2

C.

2HF + N2F2 \(\to\) N2H2F3

D.

HF + 2N2F2 \(\to\) N4HF2

Correct answer is B

No explanation has been provided for this answer.

940.

The Avogadro number of 24g of magnesium is the same as that of

A.

1g of hydrogen molecules

B.

16g of oxygen molecules

C.

32g of oxygen molecules

D.

35.5g of chlorine molecules

Correct answer is C

24mg = 1 mole of magnesium and

32g of O2 = mole of O2