Answer:
A. Molarity will increase .
Explanation:
Molarity = moles of solute per litre of solution
= moles of solute / volume of solution
If evaporation occurs , volume of solution decreases and moles of solute remains constant . Hence denominator decreases and numerator remains constant .
Hence the molarity increases .
<u>Answer:</u> The Henry's law constant for oxygen gas in water is 
<u>Explanation:</u>
To calculate the molar solubility, we use the equation given by Henry's law, which is:

where,
= Henry's constant = ?
= solubility of oxygen gas = 
= partial pressure of oxygen gas = 2.1 atm
Putting values in above equation, we get:

Hence, the Henry's law constant for oxygen gas in water is 
N = given mass/ molar mass.
n = number of moles
given mass = 2.47 g
molar mass = 197 g/mol
n = 2.47 / 197
n = 0.01253 moles.
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Chemical energy being changed into light energy would happen during phototsynthesis