Answer : The percent by mass of the solution is 7.81 %
Explanation : Given,
Mass of NaCl = 8.75 g
Mass of solution = 112.0 g
Now we have to determine the percent by mass of the solution.

Putting values in above equation, we get:

Therefore, the percent by mass of the solution is 7.81 %
Answer:
Dana filtered the sample and larger granules of the sample were left behind.
Explanation:
If a substance is pure, it will have a uniform composition throughout. It will not separate into particles of various sizes.
One of the characteristics of pure substances is that they are homogeneous. A mixture is definitely made up of particles of various sizes.
Since the particles was filtered and larger granules were left behind, the sample has been separated by a physical method (filtration). Only a mixture can be separated by physical methods. It is not a pure substance.
Use PV=nRT to find V assuming n is one and R= 8.31 then use the answer to find P2
Each isotope of Oxygen has a different number of neutrons
<h3>Further explanation
</h3>
The elements in nature have several types of isotopes
Atomic mass is the average atomic mass of all its isotopes
Isotopes are atoms has the same number of protons but has a different number of neutrons.
So Isotopes are elements that have the same Atomic Number (Proton)
Some of the isotopes of oxygen are:

Each isotope has 8 protons and 8 electrons but has a different number of neutrons
For O-16: number of neutrons = 16-8 = 8
For O-17: number of neutrons = 17-8 = 9
For O-18: number of neutrons = 18-8 = 10
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