Chemistry Past Questions And Answers
In the diagram below. X is
- A) SO3
- B) SO2
- C) S
- D) H2S
Which of the following compounds has the highest ionic character?
- A. PCI5
- B. SiCI4
- C. AICI3
- D. KCI
The postulate that molecules are in constant random motion best explains why liquids
- A. can undergo solidification
- B. maintain their volumes
- C. are incompressible
- D. have no characteristic shape
(a)(i) Draw and label a diagram to illustrate the preparation and collection of dry chlorine gas in the laboratory.
(ii) Statetwo uses of chlorine.
(b) Describe the preparation of hydrogen from water gas.
(i) Name thechief ore of aluminium.
(ii) Why is the ore purified?
(iii) Name the electrode used in the electrolysis.
(iv) Give one reason why cryolite, NaAlF\(_6\), is added to the electrolyte.
(c) Namethree products obtaineddirectly from the destructive distillation of coal.
View Discussion (0)WAEC 2020 THEORYWhich of the following is a primary constituent of crude oil?
- A. Pentane
- B. Ethanol
- C. Heptane
- D. Methane
Ethene is produced from ethanol by
- A. decomposition
- B. hydrolysis
- C. ozonolysis
- D. dehydration
A complex salt is
- A)KAl(SO\(_4\))\(_2\).12H\(_2\)O
- B)Cu(NH\(_3\))4Cl\(_2\)
- C)K\(_2\)S\(_2\)O\(_3\).5H\(_2\)O
- D)Mg(OH)Cl
How many electrons are removed from Cr How many electrons are removed from Cr2- when it is oxidized to CrO42-?-
- A. 0
- B. 2
- C. 4
- D. 8
The oxidation of ammonia in excess air produces
- A) NO
- B) N2O
- C) NO2
- D) N2O4
When Magnesium reacts with oxygen, heat is
- A. absorbed and the reaction is endothermic
- B. evolved and the reaction is endothermic
- C. evolved and the reaction is exothermic
- D. absorbed and the reaction is exothermic