Practice General concepts of chemistry - general science mcq Online Quiz (set-1) For All Competitive Exams
Q-1) In the following equations : NaCO3 + xHCL ⟶ 2NaCl + CO2 + H2O, the value x is
(a)
(b)
(c)
(d)
Na2CO3 2HCl ⟶ 2NaCl CO2 + H2O
Q-2) The total number of atoms represented by the compound CuSO4 .5H2O is
(a)
(b)
(c)
(d)
1 atom of Cu + 1 atom of sulphur + 9 atoms of oxygen + 10 atoms of hydrogen.
Total number of atoms in the compound is 21.
Q-3) Which of the following does not corrode when exposed to the atmosphere?
(a)
(b)
(c)
(d)
Gold is a noble metal.
Q-4) Which one is a bivalent ion?
(a)
(b)
(c)
(d)
Ca++ and S– –
Q-5) Slow eating away of iron articles in the presence of moist air is called
(a)
(b)
(c)
(d)
Rusting is a process in which iron gets converted into hydrated iron oxide in presence of moisture.
$2Fe + 3/2O_2 + xH_2O ⟶ {Fe_2O_3.xH_2O} ↙ {rust}$
Q-6) In the reaction : PbO + C ⟶ Pb + CO
(a)
(b)
(c)
(d)
In this carbon reduces PbO to Pb so carbon (C) is reducing agent (reductant) PbO acts as oxidising agent (oxidant) as it oxidises C to CO.
Q-7) The branch of chemistry which deals with study of physical properties and conditions is
(a)
(b)
(c)
(d)
Q-8) Which of the following is most unreactive ?
(a)
(b)
(c)
(d)
Mg++ (12 – 2 = 10e– ) = 2, 8
Hence have complete octel hence inert.
Q-9) The observation that does not indicate a chemical reaction is
(a)
(b)
(c)
(d)
A chemical reaction is generally accompanied by a change of temperature, colour or evolution of a gas.
Q-10) $Na_2S_2O_3$ represent the compound
(a)
(b)
(c)
(d)
Q-11) CuO + H2 ⟶ Cu + H2O Above reaction is an example of
(a)
(b)
(c)
(d)
It involves oxidation and reduction.
Q-12) A molal solution is one that contains 1 mole of a solute in
(a)
(b)
(c)
(d)
Molal solution contains 1 mole of solute in 1000 g solvent.
Q-13) Chemical equations are balanced in accordance with the
(a)
(b)
(c)
(d)
Q-14) The reactions in which two compounds exchange their radicals to form two new compounds are called
(a)
(b)
(c)
(d)
Q-15) A redox reaction is one in which -
(a)
(b)
(c)
(d)
Q-16) Chemical formula of Aluminium sulphate is
(a)
(b)
(c)
(d)
Q-17) Which is not a balanced equation ?
(a)
(b)
(c)
(d)
2Fe + 3Cl2 ⟶ 2FeCl3 (balanced chemical eqn.)
Q-18) Which of the following is not an endothermic process?
(a)
(b)
(c)
(d)
Dissolution of conc. H2SO4in water produces a lot of heat.
Q-19) Which of the following involves combination of two elements?
(a)
(b)
(c)
(d)
Both Na and O2 are elements.
Q-20) The chromate and dicharomate ions are respectively
(a)
(b)
(c)
(d)