Chemical Reactions and Equations — Science STD 10 — Question

Substitute formulae for names and balance the following equation:
Calcium carbonate reacts with hydrochloric acid to produce calcium chloride, water and carbon dioxide gas.

What happens when ethanol is oxidised with alkaline potassium permanganate (or acidified potassium dichromate)? Write the equation of the reaction involved.

What is the unit of refractive index?

Name the rule which gives the direction of induced current.

Name the agent which decomposes animal dung into biogas.

What type of chemical reactions are represented by the following equations?
A + BC → AC + B

Name two metals which are found in nature mainly in the free state (as metallic elements).

Name the phenomenon which is made use of in an electric generator.

Name one property which is characteristic of (a) metals, and (b) non-metals.

Write down the electronic configuration of (i) sulphur atom, and (ii) sulphide ion. (At. No. of S = 16)