Questions
4
What happens when an acid reacts with metal oxide?
Answer: Salt and water is formed
5
Which statement is correct regarding acids?
I. Acid is a molecule which donates a proton or accepts electron pair in reactions.
II. Acid increases the concentration of hydrogen atoms or hydronium atoms in water.
III. Acids have a pH value of less than 7.
IV. The acid in the stomach helps in the digestion of food.
Answer: All the above
6
Which of the following is a battery acid?
Answer: Sulphuric acid diluted with water
7
Red litmus paper turns into which colour in basic/alkaline conditions?
Answer: Blue colour
10
Which of the following is true about Alkalis?
Answer: Bases which are soluble in water are called alkalis
13
The water of crystallisation is the fixed number of
Answer: water molecules present in one formula unit of a salt
14
Why is calcium sulphate hemihydrates called Plaster of Paris?
Answer: Because of its large deposits in the Paris
15
Name the substance which on treatment with chlorine yields bleaching powder.
Answer: Calcium hydroxide
16
A solution reacts with crushed egg-shells to give a gas that turns lime-water milky. The solution contains
Answer: HCl
17
Which one of the following types of medicines are used for treating indigestion?
Answer: Antacid
18
In the presence of normal acids, Phenolphthalein colour remains
Answer: Colourless
