1. The substance not likely to contain CaCO3 is a) Dolomite b) A marble statue c) Calcined gypsum d) Sea shells.
2. Gas A, obtained above is a reactant for a very important biochemical process which occurs in the presence of sunlight. Identify the name of the process – a) Respiration b) Photosynthesis c) Transpiration d) sphotolysis
3. Calcium oxide can be reduced to calcium, by heating with sodium metal. Which compound would act as an oxidizing agent in the above process? a) Sodium b) sodium oxide c) calcium d) calcium oxide
4. What will happen if we take dry HCl gas instead of aqueous solution of HCl? a) Reaction will occur faster. b) Reaction will not occur. c) Reaction rate will be slow d) Reaction rate will remain the same.
5. Identify the types of chemical reaction occurring during the combustion of fuel: a) Oxidation & Endothermic reaction b) Decomposition & Exothermic reaction c) Oxidation & Exothermic reaction d) Combination & Endothermic reaction
6. A student while walking on the road observed that a cloud of black smoke belched out from the exhaust stack of moving trucks on the road.’ Choose the correct reason for the production of black smoke: a) Limited supply of air leads to incomplete combustion of fuel b) Rich supply of air leads to complete combustion of fuel. c) Rich supply of air leads to a combination reaction. d) Limited supply of air leads to complete combustion of fuel.
7. Predict the pH value of the water of river Yamuna if the reason for froth is high content of detergents dissolved in it. a) 10-11 b) 5-7 c) 2-5 d) 7
8. High content of phosphate ion in river Yamuna may lead to: a) decreased level of dissolved oxygen and increased growth of algae b) decreased level of dissolved oxygen and no effect of growth of algae c) increased level of dissolved oxygen and increased growth of algae d) decreased level of dissolved oxygen and decreased growth of algae
9. If a sample of water containing detergents is provided to you, which of the following methods will you adopt to neutralize it? a) Treating the water with baking soda b) Treating the water with vinegar c) Treating the water with caustic soda d) Treating the water with washing soda
10. In which of the parts would you find anaerobic bacteria a) A b) B c) C d) D
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