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.
Which of these salts will produce its metal, oxygen and nitrogen (IV) oxide on heating?
Silver and trioxonitrate (V)
Sodium trioxonitrate (V)
Calcium trioxonitrate (V)
Lithium trioxonitrate (V)
Correct answer is A
No explanation has been provided for this answer.
Which of these gases can be dried with concentrated H2SO4?
HBr
H2S
NH3
SO2
Correct answer is D
In the preparation of \(SO_{2}\), we have the resultant reaction from heating the mixture of \(Na_{2}SO_{3}\) and \(HCl\) as:
\(Na_{2}SO_{{3}{(aq)}} + 2HCl_{(aq)} \to 2NaCl_{(aq)} + H_{2}O_{(l)} + SO_{{2}{(g)}}\)
Passing the gas evolved through conc. \(H_{2}SO_{4}\), we collect \(SO_{2}\) by DOWNWARD DELIVERY, leaving \(NaCl\) in the flask.
NaCI(s) + H2SO4(I) → HCI(g) + NaHSO4(s).
In the reaction above, H2SO4 behaves as?
a strong acid
an oxidizing agent
a good solvent
a dehydrating agent
Correct answer is A
No explanation has been provided for this answer.
remains the same
drops
increases by 1%
increases by 99%
Correct answer is B
No explanation has been provided for this answer.
-42 KJ mol-
+42 KJ mol-
-262 KJ mol-
+262 KJ mol-
Correct answer is A
Standard enthalpy change of a process = ∆H° process = ∆H° F reactant - DF° products