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.
34.0
31.0
20.0
14.0
Correct answer is B
Molecular Mass = Vapour density x 2 = 17.0 x 2 = 34.0
∴ Relative Atomic Mass of X in XH3 = 34 - 3
= 31.0 ∴ x = 31.0
constant composition
conservation of mass
reciprocal proportions
multiple proportions
Correct answer is D
No explanation has been provided for this answer.
11%
31%
35%
69%
Correct answer is B
Reaction for the equation:
\(2H_{2} + O_{2} \to 2H_{2} O\)
\(2 vol : 1 vol : 2 vol\)
Hence, 2 volumes of Hydrogen is needed for the reaction with Oxygen to produce steam (water).
\(\therefore 12cm^{3} O_{2} \to 2 \times 12cm^{3} = 24cm^{3} H_{2}\)
\(\text{Excess of Hydrogen} : 35 cm^{3} - 24 cm^{3} = 11 cm^{3}\)
\(\text{% Hydrogen left after the reaction} = \frac{11}{35} \times 100% = \frac{220}{7} = 31.48% \)
\(\approxeq 31% \)
The relatively high boiling points of alkanols are due to?
ionic bonding
aromatic character
covalent bonding
hydrogen bonding
Correct answer is D
No explanation has been provided for this answer.
An example of a secondary amine is?
propylene
di-butylamine
methylamine
trimethylamine
Correct answer is B
No explanation has been provided for this answer.