11) The mass number of a nucleus is
a) always less than its atomic number
b) the sum of the number of protons and neutrons present in the nucleus
c) always more than the atomic weight
d) a fraction
12) The most important ore of aluminium is
a) bauxite
b) magnetite
c) haematite
d) monazite
13) When TEL (Tera Ethyl Lead) is added to petrol :
a) It increases the B.P of petrol
b) Increases the aniti-knocking rating
c) Decreases the B.P of petrol
d) Decreased the ani-kncking rating
14) When water is added to anhydrous white copper sulphate, the color will change to :
a) Yello
b) Green
c) Blue
d) Red
15) The oil used in the froth floatation process is
a) Coconut oil
b) Olive oil
c) Kerosene
d) Pine Oil
16) The gas used in the manufacture of vanaspati from vegetable oil is
a) hydrogen
b) oxygen
c) nitrogen
d) carbon dioxide
17) The octane number of zero is assigned to
a) 2-methyl octane
b) n-heptane
c) iso-octane
d) 3-methyl octane
18) The most important ore of aluminium is
a) bauxite
b) magnetite
c) haematite
d) monazite
19) The macro-nutrient provided by inorganic fertilization are :
a) C, Fe, B
b) C, N, P
c) N, P, K
d) Mg, Zn, Fe
20) Which of the following is the main ingredient of cement?
a) Limestone
b) Silica Clay
c) Gypsum
d) Ash