<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 
Answer:
(12×4)+(1×2)=50
Explanation:
mass of Carbon is 12....mass of hydrogen is 1
150/30 = 5
HF1 20/2 = 10
HF2 10/2 = 5
HF3 5/2 = 2.5
HF4 2.5/2 = 1.25
HF5 1.25/2 = 0.625
Answer: 0.63g
Protists belong to the group eukaryotes (having their DNA enclosed
inside the nucleus). They are not plants, nimals or fungi but they act like
one. They can be in general subgroups such as unicellular algae, protozoa and
molds. They thrive in environments with little sunlight. The answer is
letter B.
Mn+2 is cation and CO3 is anion
hope it help