Question

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

Answer 1

2. Hydrogen gas burns with a pop sound. So placing a candle there will tell us.
3. Gain of O2 and loss of H2 is oxidation. It is Exothermic.
EG: Cu + O2 -------> 2CuO
4. 2AgCl in sunlight gives rise to 2Ag + Cl2
5. CaCO3 on heat gives rise to CaO + CO2( You can find activity in Page-8 NCERT)