Metals and Non-Metals — Science STD 10 — Question

Name three products of the chlor-alkali process. State two uses of each of these products.

Explain giving one example, how highly reactive metals (which are high up in the reactivity series) are extracted.

A silver article generally turns black when kept in the open for a few days. The article when rubbed with toothpaste again starts shining.

1. Why do silver articles turn black when kept in the open for a few days? Name the phenomenon involved.
2. Name the black substance formed and give its chemical formula.

Esters are sweet-smelling substances and are used in making perfumes. Describe an activity for the preparation of an ester with the help of a well labelled diagram. Write an equation for the chemical reaction involved in the formation of the ester. Also write the names of all the substances involved in the process of esterification.

Ethene is formed when ethanol at 443K is heated with excess of concentrated sulphuric acid. What is the role of sulphuric acid in this reaction? Write the balanced chemical equation of this reaction.

Explain giving chemical equation, how are esters prepared? Specify any one property and one use of esters.

What is a homologous series? Explain with an example.

What happens when silver chloride is exposed to sunlight? Write a chemical equation for this reaction. Also give one use of such a reaction.

Draw the electron dot structure of ethyne and also draw its structural formula.

Giving their structures, state the number of single bonds, double bonds and triple bonds in the following compounds:

1. Ethyne.
2. Ethene.
3. Benzene.