11.3 Unsaturated Hydrocarbons — Chemistry STD 10 — Question

What is the Vital force theory? Why was it discarded?

Explain with the help of a balanced equation, the brown ring test for nitric acid.

The percentage composition of a gas is : Nitrogen 82.35%, Hydrogen 17.64%.
Find the empirical formula of the gas. [N = 14, H = 1]

Identify the term or substance based on the descriptions given below :
(i) Ice like crystals formed on cooling an organic acid sufficiently.
(ii) Hydrocarbon containing a triple bond used for welding purposes.
(iii) The property by virtue of which the compound has the same molecular formula but different structural formulae.

State how the following conversions can be carried out :
(i) Ethyl chloride to ethyl alcohol.
(ii) Ethyl chloride to ethene.
(iii) Ethene to ethyl alcohol.

What is observed when :
(i) Hydrogen sulphide gas is passed through lead acetate solution?
(ii) Neutral litmus solution is added to sodium hydrogen carbonate solution?
(iii) A small piece of iron is placed in copper sulphate solution?

Write the equations involved in Ostwald process.

A compound has O=61.32%, S= 11.15%, H=4.88% and Zn=22.65%.The relative molecular mass of the compound is 287 amu. Find the molecular formula of the compound, assuming that all the hydrogen is present as a water of crystallization.

Complete the table:

Indicator	Neutral	Acidic	Alkaline
Litmus Phenolphthalein	Purple Colourless