1000 Best General Science MCQ-Questions
Q17). The gases used in different types of welding would include
a).oxygen and hydrogen
b).oxygen, hydrogen, acetylene and nitrogen
c).oxygen, acetylene and argon
d).oxygen and acetylene
Correct Answer:
oxygen and acetylene
Explanation:
Q18). The property of a substance to absorb moisture from the air on exposure is called
a).osmosis
b).deliquescence
c).efflorescence
d).desiccation
Correct Answer:
deliquescence
Explanation:
Q19). In which of the following activities silicon carbide is used?
a).Making cement and glass
b).Disinfecting water of ponds
c).cutting very hard substances
d).Making casts for statues
Correct Answer:
cutting very hard substances
Explanation:
Q20). The average salinity of sea water is
a).0.03
b).0.035
c).0.025
d).0.02
Correct Answer:
0.035
Explanation:
Q21). When an iron nail gets rusted, iron oxide is formed
a).without any change in the weight of the nail
b).with decrease in the weight of the nail
c).with increase in the weight of the nail
d).without any change in colour or weight of the nail
Correct Answer:
with increase in the weight of the nail
Explanation:
Q22). Galvanised iron sheets have a coating of
a).lead
b).chromium
c).zinc
d).tin
Correct Answer:
zinc
Explanation:
Q23). Among the various allotropes of carbon,
a).coke is the hardest, graphite is the softest
b).diamond is the hardest, coke is the softest
c).diamond is the hardest, graphite is the softest
d).diamond is the hardest, lamp black is the softest
Correct Answer:
diamond is the hardest, graphite is the softest
Explanation:
Q24). The group of metals Fe, Co, Ni may best called as
a).transition metals
b).main group metals
c).alkali metals
d).rare metals
Correct Answer:
transition metals
Explanation: