1. OMTEX CLASSES SCIENCE AND TECHNOLOGY
The Magic of Chemical Reactions
Fill in the blanks
Match the following
Define
Balanced equation.
Endothermic reaction.
Exothermic reaction.
Corrosion
Neutralization reaction.
Reduction reaction.
Oxidation reaction.
Redox reaction.
Double displacement reaction.
Decomposition reaction.
2. OMTEX CLASSES SCIENCE AND TECHNOLOGY
Combination reaction.
Chemical equation.
Word equation.
Products.
Reactants.
Answer the following
What is the importance of chemical equation?
What do you observe when H2S gas is passed through Cadmium Chloride
solution? Name the type of reaction
What do you understand by the term "Redox Reactions"? Explain with one
example
What is corrosion? Do gold ornaments corrode? Justify
Give Scientific Reasons.
Grills of doors and windows are always painted before they are used
Physical states of reactants and products are mentioned while writing a
chemical equation.
Potassium Ferrocyanide is stored in dark coloured bottles and kept away
from sunlight
Iron articles rust readily whereas steel which is also mainly made of iron will
not undergo corrosion.
3. OMTEX CLASSES SCIENCE AND TECHNOLOGY
Edible oil is not allowed to stand for a long time in an iron or tin container
Edible oil is not allowed to stand for a long time in air.
Formation of a compound is a chemical change.
Conversion of ice into water is a physical change.
Chemical change is always associated with exchange of energy.
Answer in Brief
We feel fresh while on a morning walk in natural surroundings. Why don't we
feel the same after 10 a.m. and during rush hours? Write a chemical reaction
to support your statement?
Explain the following terms
Rancidity, Endothermic Reactions, Redox reaction, Neutralization
Take finely powdered Zinc and allow it to react with CuSO4 solution. Then
take Zinc granules and carry out the same reaction. Which reaction will take
place faster and why?