Page 121 - ICSE Chemistry 8

6 Chemical Reactions

Learning Outcomes Key Concepts
Students will be able to
• Chemical Reactions
• describe diff erent types of chemical reac ons with examples.
• Types of Chemical
• iden fy the type of chemical reac on.
Reactions
• iden fy diff erent oxides as basic, acidic, amphoteric or neutral.
• Reactivity or Activity
• explain the eff ect of heat on oxides of some metals.
Series of Metals
• Decomposition
Reactions to Form Oxides
• Classifi cation of Oxides

Warm Up Activity
Based on your previous knowledge, answer the following ques ons.

2Na + 2H O  2NaOH + H 2
2
1. Name the reactants in the reac on. _____________________________
2. Name the products in the reac on. _____________________________
3. What does the arrow represent? ________________________________

CHEMICAL REACTIONS

A chemical reac on is a process in which new substances with new proper es are formed. It is a change
that takes place when elements and compounds react with other to form new products. During a chemical
reac on, rearrangement of atoms takes place between the reac ng substances to form new substance(s)
having en rely diff erent proper es. Chemical reac ons involve breaking of old chemical bonds which
exist between the atoms of reac ng substances and then making of new chemical bonds between the
atoms of new substance(s).

Substances that take part in a chemical reac on are called reactants and the substances produced in the
reac on are called products.

The representa on of a chemical reac on using symbols or chemical formulae for the reactants and
products is known as a chemical equa on.

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