Answer: only Br2.
Justification.
In a chemical reaction the element that gains electrons experiments a reduction in its oxidation state, that is why it is said that it is reduced.
So, to know what element is being reduced you need to calculate the oxidation states of the elements involved.
Here I indicate the oxidation states of each element if the reaction putting them inside parenthesis:
Reactants side Products side
K (0) K (1+)
Br (0) Br(1-)
So, K lost one electron, increasing its oxidation statefrom 0 to 1+, meaning that it is being oxidized.
And, each atom of Br gained one electron, reducing its oxidation state from 0 to 1-, meaning it is being reduced.
Therefore, the answer is that Br2 is the substance being reduced.
Answer:
C
Explanation:All the other answers are wrong
Answer:
Yes, a chemical change occurs.
Explanation:

CaSO4 is insoluble in the water, so a chemical reaction or chemical change occurs.
Zn + H₂SO₄ = ZnSO₄ + H₂
answer (3) <span>single replacement
hope this helps!</span>
The moles of ammonium nitrate needed to dissolve 0.35 moles
The moles of water that will react is 0.35 moles as due to ratio
so mass of water will be 0.35 x 18=6.3g
MASS OF WATER WILL BE 6.3 g