This document discusses chemical reactions and equations from a chemistry chapter. It identifies signs of a chemical reaction such as changes in state, color, gas evolution, temperature, or precipitate formation. A chemical equation represents a reaction using symbols for elements and shows the reactants and products, such as the combustion reaction of methane and oxygen forming carbon dioxide and water.

1. My notes
Of chemistry
Chapter 1 (chemical reaction and
equation )

2. Chemical reaction
Identification of chemical reaction :
Change in state
Change n colour
Evolution of gas
Change in temperature
Formation of precipitate
Chemical equation
A system in which reaction of element in their symbol form
Eg methane + oxygen carbon dioxide + water
Ch4 + 2o2 Co2 + 2h 2o
writing an chemical equation