Science Quiz- 3 important mcq for class 10

Science

Quiz

 

1. The most poisonous product formed by incomplete combustion of fossil fuels is
   1.   Carbon dioxide
   2.   Nitrogen dioxide
   3.   Carbon monoxide
   4.   Sulphur dioxide
2. Identify ‘x’, ‘y’ and ‘z’ in the following reaction:
   2KClO3(x) ---------> 2KCl(x) + O2 (z)
   This reaction take place in presence of (y).
   1.   x = gas; y = reaction condition, z = gas
   2.   x = solid; y = liquid; z = gas
   3.   x = number of moles of KClO3; y = reaction condition; z = no. of molecules of oxygen.
   4.   x = physical state of KClO3 and KCl; y = reaction condition; z = physical state of O2.
3. An element ‘X’ with atomic number 11 forms a compound with element ‘Y’ with atomic number 8. The formula of the compound formed is
   1.   XY
   2.   X2Y
   3.   XY2
   4.   X2Y3
4. A compound ‘A’ is used in the manufacture of cement. When dissolved in water, it evolves a large amount of heat and forms compound ‘B’. Identify A and B.
   1.   A= CaO,B= Ca(OH)2
   2.   A=Ca(OH)2, B=CaO
   3.   A=MgO, B= Mg(OH)2
   4.   A=Mg(OH)2, B= MgO
5. A visually challenged student, has to perform a lab test to detect the presence of acid in a given solution. The acid-base indicator preferred by him will be:
   1.   Blue litmus
   2.   Clove oil
   3.   Red cabbage extract
   4.   Hibiscus extract
6. An aqueous solution ‘A’ turns phenolphthalein solution pink. On addition of an aqueous solution ‘B’ to ‘A’, the pink colour disappears. Which of the following statement is true for solution ‘A’ and ‘B’?
   
   1.   A is strongly basic and B is a weak base.
   2.   A is strongly acidic and B is a weak acid.
   3.   A has pH greater than 7 and B has pH less than 7.
   4.   A has pH less than 7 and B has pH greater than 7.
7. In which of the following the identity of initial substance remains unchanged?
   1.   Curdling of milk
   2.   Formation of crystals by process of crystallisation
   3.   Fermentation of grapes
   4.   Digestion of food
8. Several factories were pouring their wastes in rivers A and B. Water samples were collected from these two rivers. It was observed that sample collected from river A was acidic while that of river
   B was basic. The factories located near A and B are
   1.   soaps and detergents factories near A and alcohol distillery near B
   2.   soaps and detergents factories near B and alcohol distillery near A
   3.   lead storage battery manufacturing factories near A and soaps and detergents factories
      near B
   4.   lead storage battery manufacturing factories near B and soaps and detergents factories
      near A
9. An element ‘X’ is forming an acidic oxide. Its position in Modern Periodic Table will be
   
   1.   Group 1 and Period 3 (b)
   2.   Group 2 and Period 3
   3.   Group 13 and Period 3
   4.   Group 16 and Period 3
10. Isotopes are
    1.   Atoms of an element with similar chemical properties but different atomic masses.
    2.   Atoms of different elements with similar chemical properties but different atomic masses.
    3.   Atoms of an element with different chemical properties but same atomic masses.
    4.   Atoms of different elements with different chemical properties but same atomic masses.