It's most likely to bond with chlorine.
Answer
Part A:
Given equation:

The above equation is an example of a double replacement reaction. A double replacement (or double displacement) reaction is a reaction in which the positive and negative ions of two ionic compounds exchange.
Note: The oxidation number of:
K = +1
I = -1
Ba = +2
S = -2
So, the complete chemical equation including phases of the given reaction is:

Part B:
Given equation:

Also, the equation is an example of a double replacement reaction.
Note: The oxidation number of:
K = +1
Cl = -1
Ca = +2
S = -2
The complete chemical equation including phases of the given reaction is:
C) Humidity.
The amount of water vapor in the air is called humidity. Don't get it confused with relative humidity, its <span>the amount of water vapor present in air expressed as a percentage of the amount needed for saturation at the same temperature.
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