1. Carbon exists in the atmosphere in the form of _____.
A. Carbon monoxide only
B. Carbon monoxide in traces and carbon dioxide
C. Carbon dioxide only
D. Coal
ANSWER:C.Carbon dioxide only
SOLUTION :Therefore, option(C) is correct. i.e., Carbon exists in the atmosphere in the form of carbon dioxide only.
2. A molecule of ammonia (NH3) has ________.
A. Only single bonds
B. Only double bonds
C. Only triple bonds
D. Two double bonds and one single bond
ANSWER:A.Only single bonds
SOLUTION:So, baking soda does not contain water of crystallization.
3. Buckminsterfullerence is an allotropic form of _________
A. Phosphorus
B. Sulphur
C. Carbon
D. Tin
ANSWER : C.Carbon
SOLUTION: Buckminsterfullerene is an allotropic form of the element carbon, and contains 60 carbon atoms joined in a spherical structure.
4. Oils on treating with hydrogen in the presence of palladium or nickel catalyst form fats. This is an example of ________.
A. Addition reaction
B. Substitution reaction
C. Displacement reaction
D. Oxidation reaction
ANSWER:A.Addition reaction
SOLUTION:When oils are treated with hydrogen in the presence of a palladium or nickel catalyst to form fats, it is an example of an addition reaction.
5. In which of the following compounds ——- OH is the functional group?
A. Butanone
B. Butanol
C. Butanoic acid
D. Butanal
ANSWER:B.Butanol
SOLUTION:The functional group -OH is found in alcohols, which are organic compounds that have alcohol-like characteristics. The suffix “-ol” is used for alcohols, such as butanol and ethanol.
6. The soap molecule has a __________.
A. Hydrophilic head and a hydrophobic tail
B. Hydrophobic head and a hydrophilic tail
C. Hydrophobic head and a hydrophobic tail
D. Hydrophilic head and a hydrophilic tail
ANSWER:A.Hydrophilic head and a hydrophobic tail
SOLUTION:A soap molecule has a hydrophilic head and a hydrophobic tail
7. Chlorine reacts with saturated hydrocarbons at room temperature in the ___________.
A. Absence of sunlight
B. Presence of sunlight
C. Presence of water
D. Presence of hydrochloric acid
ANSWER:B.Presence of sunlight
SOLUTION :
Therefore, chlorine reacts with saturated hydrocarbons at room temperature in the presence of sunlight.
8. Ethanol reacts with sodium and forms two products. These are_____________.
A. Sodium ethanoate and hydrogen
B. Sodium ethanoate and oxygen
C. Sodium ethoxide and hydrogen
D. Sodium ethoxide and oxygen
ANSWER: C.Sodium ethoxide and hydrogen
SOLUTION:Ethanol acts as when it reacts with sodium metal to form sodium ethoxide and hydrogen gas.
9. Vinegar is a solution of ____________.
A. 50% – 60% acetic acid in alcohol
B. 5% – 8% acetic acid in alcohol
C. 5% – 8% acetic acid in water
D. 50% – 60% acetic acid in water
ANSWER:C.5% – 8% acetic acid in water
SOLUTION:Vinegar is an aqueous solution of acetic acid and trace chemicals that may include flavourings. Vinegar typically contains 5–8% acetic acid by volume.
10. The first member of alkyne homologous series is________.
A. Ethyne
B. Ethene
C. Propyne
D. Methane
ANSWER: A.Ethyne
SOLUTION:
Ethyne (\(C_{2}H_{2}\)) is the first member of the alkyne homologous series. It’s a hydrocarbon with two carbon atoms bonded by a triple bond, as shown in the structure H-C≡C-H. Ethyne is also known as acetylene and is used in arc welding as oxyacetylene gas.