Answer:
heat energy are absorbed by water molecules and it is used to change the molecules from liquid to gas? if thats what your asking.
Explanation:
<span>Nitrogen trifluoride - NF3.
1 mol NF3 contains 1 mol atoms of Nitrogen
2.49 mol NF3 contains 2.49 mol atoms of Nitrogen
1 mol ---- 6.02 *10²³ atoms
2.49 mol ----- 2.49*6.02*10²³ = 15.0*10²³ atoms of N</span>
Answer: The mass of air present in the room is 37.068 kg
Explanation : Given,
Length of the room = 10.0 ft
Breadth of the room = 11.0 ft
Height of the room = 10.0 ft
To calculate the volume of the room by using the formula of volume of cuboid, we use the equation:

where,
V = volume of the room
l = length of the room
b = breadth of the room
h = height of of the room
Putting values in above equation, we get:

Conversion used : 
Now we have to calculate the mass of air in the room.



Conversion used : (1 kg = 1000 g)
Therefore, the mass of air present in the room is 37.068 kg
Answer:
The correct answer is 5.30 * 10^-4 mol per L.
Explanation:
Based on Henry's law, in a solution solubility of the gas is directly proportional to the pressure, that is, C is directly proportional to P. Here P is the pressure and C is the concentration of the dissolved gases.
Therefore, it can be written as,
C2/C1 = P2/P1
Here, C1 is 6.8 * 10^-4 mol/L, P1 is 1 atm and P2 is 0.78 atm, then the value of C2 obtained by putting the values in the equation,
C2/(6.8*10^-4) = 0.78/1
C2 = 0.78 * 6.8*10^-4
C2 = 5.30 * 10^-4 mol per L.
Hence, the concentration of dissolved nitrogen at 0.78 atm is 5.30*10^-4 mol/L.
A pure substance is a element made up of only one type of atom or molecule.