Answer:
There are
Explanation:
In this problem, we need to find the number of molecules in
mol of
.
The molar mass of
is 
No of moles = mass/molar mass
We can find mass from above formula.

Also,
No of moles = no of molecules/Avogadro number

Hence, there are
Answer:
Second one
Explanation:
I think it's the second cause there's no energy w/o heat. So it's the second.
Ok, I will help you answer but it is very hard to read could you enlarge it first?
Thanks!
NaHCO3 = No. of atoms are 1 sodium + 1 Hydrogen + 1 carbon + 3 oxygens = 6 atoms per molecule.
so a total of 3 oxygens
Answer
Calculating the mass number for an atom requires that we know the atomic number and the number of protons in the atom’s nucleus. The mass number then gives us the average weight of atoms of a given element. However, as long as the number of protons equals the number of neutrons, the values balance out and we always obtain a whole number for the mass number.
Explanation:
those 3