Answer:
If you have to choose only one answer, it is B.
Explanation:
Adding water - changes the volume of solvent
Number of moles of solute does not change because you do not adding solute.
the Molarity of solvent usually is not used.
If it is only one choice, it is B.
Out of the choices given, the correct answer would be chlorine. It is the atom with the strongest attraction for electrons in a bond formation. This is because it has the highest electronegativity among the choices.
The sum of the mass numbers and the sum of the atomic numbers balance on either side of an equation
Answer:

Explanation:
Hello there!
In this case, we can identify the solution to this problem via the Dalton's rule because the partial pressure of helium is given by:

Whereas the mole fraction of helium is calculated by firstly obtaining the moles and then the mole fraction:

Then, we calculate the partial pressure as shown below:

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The answer is definitely D