Jamb Chemistry Past Questions For Year 1981
Question 16
The brown coloration in nitric acid prepared in the laboratory can be removed by?
- A. heating the acid
- B. bubbling air through the acid
- C. cooling the acid
- D. adding a decolorizing agent
- E. adding a base
Question 17
In the reaction
C + 2HNO3 → CO2 + NO2 + NO + H2O nitric acid is acting as?
- A. a reducing agent
- B. a nitrating agent
- C. an oxidizing agent
- D. a catalytic agent
- E. a neutralizing agent
Question 18
If concentrated sulphric acid is added to sugar and warmed gently, the sugar changes from white to brown and finally to a black mas of carbon. In this reaction, concentrated sulphuric acid is acting as ?
- A. a drying agent
- B. an oxidizing agent
- C. a dehydrated agent
- D. a reducing agent
- E. a hydrolysing agent
Question 19
In the reaction of oxygen with hydrogen to produce water, which of the following statements is true?
- A. One atom of hydrogen reacts with two atoms of oxygen to give one molecule of water
- B. Two atoms of hydrogen react with two atoms of oxygen to give two molecules of water
- C. One molecule of oxygen reacts with one molecule of hydrogen to give two molecules of water
- D. One molecule of hydrogen reaccts with two molecules of oxygen to give three molecules of water
- E. One molecule of oxygen reacts with two molecules of hydrogen to give two molecules of water
Question 20
Which of the following is the electronic configuration of sodium?
(Atomic number of Na = 11)
- A. 1s2 2s22p6 3s2
- B. 1s2 2s22p6 3s2 3p1s2 2s22p6 3s1
- C. 1s2 2s22p6 3s1
- D. 1s2 2s22p6 3s°
- E. 1s2 2s22p6 4s1
