Given :
Volume of NaCl solution 2.5 L .
Molarity of NaCl solution is 0.070 M .
To Find :
How many moles are present in the solution.
Solution :
Let, n be the number of moles.
We know, molarity is given by :

So,

Therefore, number of moles of NaCl is 0.175 moles.
Mass number is the number of protons and neutrons in an atom, and it tells us about the mass of the atom in amu, or atomic mass units. Atomic mass is the average mass of all the isotopes of a certain type. It is a weighted average that takes into account the abundances of all of the different isotopes
hope this helps :)
It showed that the nucleus is positively charged, and that the atom isn't just made of electrons.
Glucose has empirical formula C6H12O6. So its formula mass can be calculated from that: 12.01x6 + 1.008x12 + 16.00x6 = 72.06 + 12.096 + 96.00 = 180.156 which needs to be rounded to two decimals to get 180.16 g/mole<span>.</span>