Atoms arent indivisible. Atoms consist of protons, electrons, neutrons, & quarks & a whole bunch of subatomic particles.
Answer:

Explanation:
1 mole of any substance contains the same number of particles. The particles can vary (atoms, molecules, formula units), but there are always 6.022*10²³ particles. In this case, the particles are formula units of potassium nitrate or KNO₃.
Let's create a ratio.

Since we are trying to find the formula units in 0.250 moles, we multiply by that number.

The units of moles of potassium nitrate cancel.

The denominator of 1 can be ignored, so we can make a simple multiplication problem.


If we round to the nearest tenth, the 0 in the hundredth place tells us to leave the 5 in the tenth place.

0.250 moles of potassium nitrate is approximately equal to 1.5*10²³ formula units of potassium nitrate and choice B is correct.
Answer:
The atmosphere, I believe.
Explanation:
First you find moles of HCl.
8.53gHCl(1 mol HCl/36.46gHCl)=0.234mol HCl
Then since molar it is mol/L you divide the number on moles of HCl by the amount of solution in L (0.372L).
Good luck!