Aqueous solution of copper sulphate reacts with aqueous ammonium hydroxide solution to give.

Enamel has calcium phosphate [Ca ₃(PO₄)₂]. When we eat sweets, they form acid in our mouth which reacts and tooth decay starts. To avoid tooth decay, we should brush our teeth after every meal. Sonu brushes his teeth twice a day whereas Monu brushes once a day only. Answer the following questions.

(i) Is toothpaste acidic, basic or neutral? Give reason.

(ii) What values are associated by Sonu, who brushes his teeth twice a day?

Dinesh is a farmer. He got pH of his soil tested and followed advice of Agricultural Scientists of 'Kissan Centre' in growing crops. He got better quality of crops this year. Answer the following questions.

(i) Why should we get our soil tested?

(ii) If soil has pH less than 7, how can we make it neutral?

(iii) What values are possessed by Dinesh?

Acetic acid was added to a solid X kept in a test tube. A colourless and odourless gas was evolved. The gas was passed through lime water which turned milky. It was concluded that.

Consider the following reaction:

Here, A, B, C and D respectively are: