One of the following is an endothermic reaction. This is :

(a) combination of carbon and oxygen to form carbon monoxide

(b) combination of nitrogen and oxygen to form nitrogen monoxide

(c) combination of glucose and oxygen to form carbon dioxide and water

(d) combination of zinc and hydrochloric acid to form zinc chloride and hydrogen

Q. Carbon combines with oxygen to form two oxides, carbon monoxide, and carbon dioxide. The ratio of the different masses of oxygen that combine with a fixed mass of carbon is 1:2, which is a simple ratio. This fact is in agreement with the:

Q. Carbon and oxygen combine to form two oxides, carbon monoxide and carbon dioxide in which the ratio of the weights of carbon and oxygen is respectively $12:16$ and $12:32$.

Q. Which of the following gases combines with the blood and prevents it from carrying oxygen?
(a) carbon monoxide
(b) carbon dioxide
(c) nitrogen oxide
(d) nitrogen trioxide

Q. Assertion :Carbon monoxide is a poisonous gas.
Reason: Carbon monoxide combines with haemoglobin to form carboxy-haemoglobin whch prevents absorption of oxygen by it.

Q.

Question 33
Write a balanced chemical equation for each of the following reactions and also classify them.

(a) Lead acetate solution is treated with dilute hydrochloric acid to form lead chloride and acetic acid solution.

(b) A piece of sodium metal is added to absolute ethanol to form sodium ethoxide and hydrogen gas.

(c) Iron (III) oxide on heating with carbon monoxide gas reacts to form solid iron and liberates carbon dioxide gas.

(d) Hydrogen sulphide gas reacts with oxygen gas to form solid sulphur and liquid water.