EASY
7th CBSE
IMPORTANT
Earn 100
Identify the acid used in the purification of metals like gold and silver.
33.33% studentsanswered this correctly
Important Questions on Acids, Bases and Salts
MEDIUM
7th CBSE
IMPORTANT
Though phosphoric acid contains three hydrogen molecules, it is a dibasic acid. Give reasons.
MEDIUM
7th CBSE
IMPORTANT
Is baking soda the same as baking powder? Support your answer.
MEDIUM
7th CBSE
IMPORTANT
"Phosphoric acid is an effective rust remover". Justify.
MEDIUM
7th CBSE
IMPORTANT
While showing some common compounds used in our daily life in the laboratory, the teacher showed sodium chloride compound and told that it is also called common salt. Next day, one of the students brought common salt from home to the laboratory and requested the teacher to show sodium chloride as well. He kept both common salt and sodium chloride in two different watch glasses and left. Next day, during lunch break the student went to the laboratory and saw that the common salt brought from home became sticky whereas the compound sodium chloride remained as it is. What would be the justification given by the teacher for the above observation?
MEDIUM
7th CBSE
IMPORTANT
Two friends Neela and Leela went to a shop, brought mango and lemon pickle of kg each respectively. Neela stored the pickle in tin-coated iron vessel, whereas Leela stored her pickle in glass vessel. After few days, Neela found that her pickle got spoiled, whereas Leela's pickle did not. Explain the reason behind it.
MEDIUM
7th CBSE
IMPORTANT
Hydrochloric acid is used to clean the metal surface before the metal surface is subjected to galvanisation. Explain.
MEDIUM
7th CBSE
IMPORTANT
Why is nitric acid used in the purification of gold?
MEDIUM
7th CBSE
IMPORTANT
Hydrated sodium sulphate and hydrated copper sulphate are taken in two air-tight containers X and Y, respectively. When blue-coloured is introduced into the two containers, there is colour change in one container. Identify the container and give reasons in support of your answer.
