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This section includes 265 Mcqs, each offering curated multiple-choice questions to sharpen your Chemistry knowledge and support exam preparation. Choose a topic below to get started.
151. |
According to collision theory, increase in temperature increases |
A. | kinetic energy of reactants |
B. | heat energy of reactants |
C. | both a and b |
D. | humidity in the air |
Answer» D. humidity in the air | |
152. |
Flour mills and coal mines need to be well ventilated because |
A. | the surface area of coal and flour needs to be digged out |
B. | coal and flour particles are scattered in the form of lumps |
C. | coal and flour particles are scattered in the form of powder |
D. | coal and flour particles can get ignited very easily |
Answer» E. | |
153. |
Uses of enzymes does not include |
A. | production of insulin |
B. | production of cancer drugs |
C. | drug to combat plague |
D. | drug to fight dwarfism |
Answer» D. drug to fight dwarfism | |
154. |
Biological catalyst to convert Hydrogen Peroxide (H₂O₂) into water (H₂O) and oxygen (O₂) is |
A. | amylase |
B. | hydrolase |
C. | catalase |
D. | protease |
Answer» D. protease | |
155. |
If heated Mg(s) is allowed to react with H₂O(l), the product formed other than H₂(g) will be |
A. | MgO(s) |
B. | MgO(aq) |
C. | Mg(OH)₂ (aq) |
D. | Mg₂O₃(s) |
Answer» B. MgO(aq) | |
156. |
Measurement of increase in concentration of reactant and increase in concentration of product over a specific time period is called |
A. | rate of reaction |
B. | equilibrium reaction |
C. | rate determining step |
D. | none of above |
Answer» B. equilibrium reaction | |
157. |
Rate of reaction approx. doubles when temperature increases |
A. | approx. 50C |
B. | approx. 10 °C |
C. | approx. 15 °C |
D. | approx. 20 °C |
Answer» C. approx. 15 °C | |
158. |
Surface area is greater in |
A. | small particles |
B. | powdered particles |
C. | larger lumps |
D. | crystals |
Answer» C. larger lumps | |
159. |
Factors affecting speed of chemical reactions does not include |
A. | pressure on reactants |
B. | particle size of reactants |
C. | concentration of reactants |
D. | volume of reactants |
Answer» E. | |
160. |
MSG (Monosodium glutamate) is added in food |
A. | as a preservative |
B. | as a food flavourer |
C. | to enable quick cooking when consumed |
D. | to add scent |
Answer» C. to enable quick cooking when consumed | |
161. |
In graph of decrease in mass against time, fastest reaction shows |
A. | steepest curve |
B. | less steep |
C. | flat curve |
D. | a plateau |
Answer» B. less steep | |
162. |
Brazil has fewer oil reserves that's why they can grow a lot of sugar cane to produce |
A. | alcohol |
B. | ethanol |
C. | glucose |
D. | sugar |
Answer» C. glucose | |
163. |
Which is incorrect about the characteristics of Group II elements? |
A. | The metals act as reducing agents. |
B. | The metals are reduced when they react. |
C. | The metals of Group II loose electrons |
D. | The metals of Group II are reactive metals |
Answer» C. The metals of Group II loose electrons | |
164. |
Sugar cubes dissolve more slowly in hot drink than granulated sugar because |
A. | surface area of sugar cubes is less |
B. | surface area of granulated sugar is more |
C. | sugar cubes are acidic |
D. | both a and b |
Answer» E. | |
165. |
The activation energy of particular reaction is the minimum energy that is must for |
A. | reaction |
B. | collision |
C. | absorption |
D. | reduction |
Answer» C. absorption | |
166. |
Adsorption refers to the |
A. | bounding of a substance to the surface of another substance |
B. | diffusion of one substance to the bulk of other substances completely |
C. | boiling of liquid at the surface |
D. | an inability to bond something at the surface |
Answer» B. diffusion of one substance to the bulk of other substances completely | |
167. |
Carbonyl compounds when oxidized easily to form carboxylic group involves |
A. | aldehydes |
B. | ketones |
C. | haloalkanes |
D. | esters |
Answer» B. ketones | |
168. |
Which statement is correct about Group-II metals who have attraction of high nuclear charge? |
A. | it is because of the greater shielding effect |
B. | it makes the loss of electrons impossible |
C. | it is because of the distance from the nucleus |
D. | it outweighs the attraction of higher nuclear charge |
Answer» E. | |
169. |
The standard enthalpy change of combustion occurs when 1 mol of substance is burnt more than |
A. | nitrogen |
B. | oxygen |
C. | carbon dioxide |
D. | helium |
Answer» C. carbon dioxide | |
170. |
The electronegativity of Chlorine (Cl₂) is |
A. | 3.04 |
B. | 3.16 |
C. | 2.2 |
D. | 2.55 |
Answer» C. 2.2 | |
171. |
In a certain volume, higher temperature |
A. | increases concentration of gases |
B. | decreases concentration of gases |
C. | liquefies the gases |
D. | the reaction may not occur at all |
Answer» B. decreases concentration of gases | |
172. |
Halogen with the highest electronegativity is |
A. | F |
B. | Br |
C. | Cl |
D. | I |
Answer» B. Br | |
173. |
Collision theory helps to explain the effects of |
A. | concentration |
B. | temperature |
C. | surface area |
D. | all of above |
Answer» E. | |
174. |
The proportion of successful collision increase with the increase in |
A. | solute |
B. | solvent |
C. | reactant |
D. | temperature |
Answer» E. | |
175. |
The rate of reaction is the change in the number of reactants or products in specific |
A. | volume |
B. | density |
C. | time |
D. | area |
Answer» D. area | |
176. |
First calculations on equilibrium were carried out by |
A. | Cato Guldberg only |
B. | Peter Waage only |
C. | John Dalton |
D. | Cato Guldberg and Peter Waage |
Answer» E. | |
177. |
The distribution of energy for temperature was given in |
A. | Boltzmann distribution |
B. | Boltzmann energy |
C. | Boltzmann temperature distribution |
D. | Boltzmann pressure |
Answer» B. Boltzmann energy | |
178. |
According to collision theory, the reaction speeds up when a frequency of reaction |
A. | decreases |
B. | increases |
C. | constant |
D. | equilibrium |
Answer» C. constant | |
179. |
The standard enthalpy change of neutralization involves the reaction of an acid with an alkali to form 1 mol of |
A. | water |
B. | oxygen |
C. | nitrogen |
D. | anhydrous salt |
Answer» B. oxygen | |
180. |
The slowest step on which overall reaction depends is |
A. | rate of reaction |
B. | rate equation |
C. | rate determining step |
D. | none of above |
Answer» D. none of above | |
181. |
Many catalysts are |
A. | noble gases |
B. | transition metals |
C. | non-metals |
D. | inert gases |
Answer» C. non-metals | |
182. |
If forward reaction is feasible then the reverse mechanism is |
A. | not feasible |
B. | possible |
C. | constant |
D. | highly probable |
Answer» B. possible | |
183. |
The pH of Mg(OH)₂ produced after Mg(s) and H₂O(l) reaction is |
A. | 1 to 4 |
B. | 5 to 7 |
C. | 8 to 11 |
D. | 12 to 14 |
Answer» D. 12 to 14 | |
184. |
Some particles collide but bounce back afterward it is called |
A. | successful collision |
B. | unsuccessful collision |
C. | successful reaction |
D. | unsuccessful reaction |
Answer» C. successful reaction | |
185. |
An average size cigarette burns in 10 seconds |
A. | in pure hydrogen |
B. | in pure oxygen |
C. | in pure carbon dioxide |
D. | at room temperature |
Answer» C. in pure carbon dioxide | |
186. |
The enthalpy change when the number of reactants gives products under standard conditions is called standard enthalpy change of |
A. | reaction |
B. | formation |
C. | combustion |
D. | neutralization |
Answer» B. formation | |
187. |
The value of Eo is known as |
A. | standard electrode potential |
B. | standard cell potential |
C. | standard charge potential |
D. | standard ion potential |
Answer» C. standard charge potential | |
188. |
Order of reaction can be predicted by knowing that the rate-determining step have what |
A. | intermediates |
B. | reactants |
C. | products |
D. | initiators |
Answer» B. reactants | |
189. |
Nitric acid is a good |
A. | oxidizing agent |
B. | reducing agent |
C. | reactant |
D. | none of above |
Answer» B. reducing agent | |
190. |
Among zinc and copper, the greater tendency to lose electrons is of |
A. | copper |
B. | zinc |
C. | aluminum |
D. | nickel |
Answer» C. aluminum | |
191. |
If the reaction is likely to occur when we say that it is |
A. | feasible |
B. | impossible |
C. | constant |
D. | malleable |
Answer» B. impossible | |
192. |
Upon reaction of metals of Group II with oxygen, electrons are lost more easily by |
A. | larger atoms of Group-II |
B. | smaller atoms of Group-II |
C. | larger atoms of Group-III |
D. | smaller atoms of Group-III |
Answer» B. smaller atoms of Group-II | |
193. |
A colorimeter helps to measure in a reaction mixture its |
A. | progress |
B. | reactants |
C. | products |
D. | temperature |
Answer» B. reactants | |
194. |
What is true about Carbon dioxide? |
A. | it enhances global warming only |
B. | it is pollutant only |
C. | it is toxic |
D. | it enhances global warming and it is pollutant |
Answer» E. | |
195. |
The system will not be in equilibrium when there is an increase in concentration of |
A. | reactants |
B. | products |
C. | catalysts |
D. | activation energy |
Answer» C. catalysts | |
196. |
Consider the reaction: Al(s) + O₂ (g) → Al₂O₃. Moles of Al(s) needed to balance the equation are |
A. | 1 |
B. | 2 |
C. | 3 |
D. | 4 |
Answer» E. | |
197. |
A saturated solution of lead (II) contains 0.99g per 100 g of water, therefore it is regarded as |
A. | saturated solution |
B. | unsaturated solution |
C. | insoluble |
D. | soluble |
Answer» D. soluble | |
198. |
The problem of enhanced global warming is due to the vast amount of CO₂ produced by a human from past |
A. | 100 years |
B. | 200 years |
C. | 300 years |
D. | 400 years |
Answer» C. 300 years | |
199. |
The condition of Mg in which it reacts violently with water is |
A. | Mg(s) while cold |
B. | Mg(s) when heated |
C. | Mg(s) at normal temperature |
D. | none of above |
Answer» C. Mg(s) at normal temperature | |
200. |
Upon the reaction: SiCl₄(l) + 2H₂O(l) → SiO₂(s) + HCl(g), the solution becomes ionic because |
A. | H⁺ are produced. |
B. | the gaseous HCl is formed |
C. | some of the HCl(g) can get dissolved in water |
D. | all of above |
Answer» E. | |