General-Studies Quiz For FCI Phase I 2022- 13th November

Q1. Which of the following can be used for removal of stains of rust on clothes?
1. H2O2
2. Oxalic acid
3. Petrol
4. Alcohol
(a) 1 and 2
(b) 2 only
(c) 3 and 4
(d) 1, 2, 3 and 4
(e) None of the above

Q2. Why is it difficult to see through fog?
(a) Rays of light suffer total internal reflection from the fog droplets
(b) Rays of light are scattered by the fog droplets
(c) Fog droplets absorb light
(d) The refractive index of fog is extremely high
(e) None of the above

Q3. The density of water varies with temperature which helps the aquatic animals to live in cold water. At what temperature is the density of water maximum?
(a) 1°C
(b) 2°C
(c) 3°C
(d) 4°C
(e) None of the above

Q4. What is the term used to denote the critical temperature at which the air becomes saturated with vapour and below which the condensation is likely to begin?
(a) Condensation point
(b) Evaporation point
(c) Dew point
(d) Point of critical temperature
(e) None of the above

Q5. When iron is rusted, it is
(a) Oxidised
(b) Reduced
(c) Evaporated
(d) Decomposed
(e) None of the above

Q6. In which one of the following situations a chemical reaction does not occur?
(a) Common salt is exposed to air
(b) Coal is burnt in air
(c) Sodium is placed in water
(d) Iron is kept in moist air
(e) None of the above

Q7. Oils are purified by
(a) Fractional distillation
(b) Steam distillation
(c) Crystallisation
(d) Vacuum distillation
(e) None of the above

Q8. What would be the best choice for window material to keep the outside heat away?
(a) Single-pane glass
(b) Double-pane glass without a gap in between
(c) Double-pane glass with water filled in between
(d) Double-pane glass with air in between
(e) None of the above

Q9. One feels heavier in a lift when the lift
(a) is going down steadily
(b) just begins to go up
(c) is moving up steadily
(d) descends freely
(e) None of the above

Q10. The lift of an air plane is based on
(a) Torricelli’s theorem
(b) Bernoulli’s theorem
(c) Law of gravitation
(d) Conservation of linear momentum
(e) None of the above

Solutions

S1.Ans. (b)
Sol. Oxalic acid is used as a rust removal agent because it forms a stable water soluble salt with ferric iron i.e., ferrioxalate ion.

S2.Ans. (b)
Sol. The rays of light are scattered by the fog droplets due to which it become difficult to see through fog.

S3.Ans. (d)
Sol. Density of water is maximum at 4°C.

S4.Ans. (c)
Sol. When air reaches the dew point at a particular pressure, the water vapour in the air is in equilibrium with liquid water which means that water vapour is condensing at the same rate at which liquid water is evaporating. Below dew point, liquid water will begin to condense.

S5.Ans. (a)
Sol. Rusting is a chemical process that results in corrosion or oxidation when oxygen metal comes in contact with a metal. It is a process in which iron turns into red iron oxide.

S6.Ans. (a)
Sol. Exposure of common salt to air is a physical change. In chemical sections, reactants produce substances which are different form the reactants No chemical realize taken plot when common salt (NaCl) is exposed to air as no new substances are produced.

S7.Ans. (b)
Sol. Oils are purified by steam distillation. In steam distillation process steam is bubbled through a heated mixture of raw material. Some of the target components will vaporize which are coded and condensed yielding a layer of oil and a layer of water.

S8.Ans. (d)
Sol. To keep the outside heat away, windows of double-pane glass with air in between is the best choice because air is the bad conductor of heat.

S9.Ans. (b)
Sol. One feels heavier in a lift when the lift just begins to go up because our body gains inertia from the position of rest and pushes up against the gravity so here the weight becomes zero and our mass makes us feel heavier.

S10.Ans. (b)
Sol. The lift of an air plane is based on Bernoulli’s theorem. Bernoulli’s theorem implies, therefore, that if the fluid flows horizontally so that no change in gravitational potential energy occurs, then a decrease in fluid pressure is associated with an increase in fluid velocity.