Answer:

Explanation:
In a single-displacement reaction, one element exchanges partners with another element in a compound.

This is a single-displacement reaction, because the element Fe exchanges partners with H in HCl.

This is not a single-displacement reaction, because it is a reaction between two compounds.
This is a double displacement reaction in which the K⁺ and H⁺ cations change partners with the anions.

This is not a single-displacement reaction. It is another double displacement reaction, in which the Na⁺ and H⁺ cations change partners with the anions.

This is a single-displacement reaction, because the element Ca exchanges partners with H in H₂O.
are not single-displacement reactions.
Answer:
a) False
b) False
c) True
Explanation:
a) Most sulfur oxides formed during combustion come from sulfur in the air: The sulfur burns in presence of oxygen to produce sulfur oxides, the source of sulfur is anthropogenic activities (Human activities).
So the given statement is false.
b) A flue gas scrubber removes SO2 pollution in a coal-fired power plant by using lime to convert the SO2 into alcohols:
False
The lime reacts with sulfur dioxide to give carbon dioxide and calcium sulfite.

c) True
c)
Answer:
81 gm
Explanation:
The mass of 1 mole is 27 g
So, Mass of 3 moles of Aluminium would be 3 × 27 = 81 gm..Thus mass of 3 Moles of Aluminium is 81 gm.
Thompson proposed a model (the plum pudding model) whereby the negatively charged corpuscles were distributed in a uniform sea of positive charge. In other words the positive charge was like the pudding and the negative charge were like raisins on the pudding.