Read the following and answer any four questions
When a silvery grey powder of a solid (A) is mixed with a powder of solid (B) no reaction occurs. But if the mixture is ignited and lighted using magnesium ribbon a reaction occurs with evolution of large amount of heat forming product (C) which settles down as liquid metal and the solid product (D) formed floats on the liquid (C). (C) in solid form reacts with moisture to form rust. The amount of heat generated during the reaction is so high that the reaction is used in welding of electric conductors, joints in railway tracks. Based on this information, answer any four questions
The reaction in which heat is generated is called as:

Options

A. Exothermic reaction
B. Endothermic reaction
C. Decomposition reaction
D. Precipitation reaction

Answer

A

Explanation

Reaction in which heat is released along with formation of products are called exothermic reactions
Example: Burning of natural gas.
`CH_(4)(g)+2O_(2)(g) to CO_(2)(g)+2H_(2)O+"Heat"`