Chemical Reactions and Equations-Sample Questions

Q1.  What happens chemically when quick lime is added to water?

Q2.  How will you test for the gas which is liberated when HCL reacts with an active metal?

Q3.  What is an oxidation reaction? Is it exothermic or endothermic? Give one example of oxidation Reaction.

Q4.  Give an example of photochemical reaction.

Q5.  Give an example of a decomposition reaction. Describe any activity to illustrate such a reaction by heating.

Q6.  Why is respiration considered as exothermic process?

Q7.  Balance the following chemical equation.

           Fe(s) +H₂O(g) = Fe₃O₄ + H₂(g)

           MnO₂ + HCL = MnCl₂ + Cl₂ + H₂O

           HNO₃ + Ca(OH)₂ = Ca(NO₃)₂ + H₂O

Q8.  On what basis is a chemical equation balanced?

Q9.  State any two observations in an activity suggesting the occurrence of a chemical reaction.

Q10.  Name a reducing agent which may be used to obtain manganese from manganese dioxide.

Q11.  What change in colour is observed when silver chloride is left exposed to sunlight? Also mention the type of chemical reaction.

Q12.  Define a combination reaction. Give one example of an exothermic combination reaction.

Q13.  What is observed when a solution of potassium iodide is added to lead nitrate solution?

              What type of reaction is this? Write a balanced chemical equation for this reaction.

Q14.  Distinguish between an exothermic and an endothermic reaction.

Q15.  Distinguish between a displacement and a double displacement reaction.

Q16.  Identify the type of reaction in the following:

              Fe + CuSO₄(aq) = FeSO₄(aq) + Cu(s)

              2H₂ + O₂ = 2H₂O