Q1. What is a redox reaction?
Q2. What is corrosion? Explain its advantage anddisadvantage.
Q3. What is rancidity? How can we reduce theproblem of rancidity?
Q4. How is corrosion different from rusting?
Q5. What is meant by endothermic and exothermic reactions? Give suitable example for each.
Q6. Define different types of chemical reaction andgive examples for each.
Q7. Why is photosynthesis considered as anendothermic reaction?
Q8. In electrolysis of water, why is the volume of gas collected over one electrode double that of the
other electrode?
Q9. What happens when water is added to solidcalcium oxide taken in a container? Write achemical formula for the same.
Q10. Give one use of quick lime.
Q11. Give three types of decomposition reaction.
Q12. Name the compound used for testing CO²gas
Answers
Answer:
Q.1 Answer: Redox is a type of chemical reaction in which the oxidation states of atoms are changed. Redox reactions are characterized by the actual or formal transfer of electrons between chemical species, most often with one species undergoing oxidation while another species undergoes reduction.
Q.2 Answer: Protection : Surface corrosion forms an oxide layer which further protects the inner metal form corrosion. Corrosion prevents corrosion : Some metals like zinc are used as sacrificial anodes to prevent corrosion to other metal. ... The main disadvantages of corrosion of metal are: Lose of metal from the surface.
Q.3 Answer: The condition produced by aerial oxidation of fats and oils in foods marked by unpleasant smell and taste is called rancidity. ... Rancidity can be prevented by adding anti -oxidants to foods containing fats and oils. 2. Rancidity can be prevented by packaging fats and oil containing foods in nitrogen gas.
Q.4 Answer: Corrosion is the process of deterioration of materials as a result of chemical, electrochemical or other reactions. Rusting is a part of corrosion and is a chemical process which results in the formation of red or orange coating on the surface of metals. ... Rust or rusting can affect only iron and its alloys.
Q.5 Answer: reaction in which heat energy is liberated by the reactants is called exothermic reaction. eg: Carbon + Oxygen gives Carbon Dioxide + Q. reaction in which heat energy is absorbed by the reactants is called endothermic reaction. eg: Nitrogen + Oxygen gives 2 nitrous oxide (2NO) -
Q.6 Answer:The five basic types of chemical reactions are combination, decomposition, single-replacement, double-replacement, and combustion. Analyzing the reactants and products of a given reaction will allow you to place it into one of these categories. Some reactions will fit into more than one category.