Question

How do you convert ${\text{0}} \cdot {\text{45 g}}$ of sodium hydroxide, ${\text{NaOH}}$ to moles?

Answer 1

Hint: Analyze the given data in question where the mass of sodium hydroxide is given. Calculate the molar mass of the sodium hydroxide and put the values in the formula of the number of moles.

Complete step by step answer:
1) First of all, let us see what has been given in the question. The mass of the sodium hydroxide is given which is ${\text{0}} \cdot {\text{45 g}}$. For the calculation of the sodium hydroxide moles, we need the value of the molar mass of sodium hydroxide.
2) The molar mass is the sum of all the masses of each individual atom present in the molecule. Now let us calculate the molar mass of sodium hydroxide which is as below,
Mass of sodium atom ${\text{23}}$ grams
Mass of oxygen atom ${\text{16}}$ grams
Mass of hydrogen atom ${\text{1}}$ grams
Now as we know the mass of all the atoms present in the molecule of sodium hydroxide we can calculate the molar mass as below,
The molar mass of sodium hydroxide $ = NaOH = Na + O + H = 23 + 16 + 1 = 40g$
3) Now as we know the molar mass of the sodium hydroxide, we can calculate the number of moles of sodium hydroxide by using the following formula,
${\text{Number of moles = }}\dfrac{{{\text{Mass given of NaOH}}}}{{{\text{Molar mass of NaOH}}}}$
Noe let us put the known values in the above formula we get,
${\text{Number of moles = }}\dfrac{{0 \cdot 45}}{{40}}$
By doing the calculation we get the values as,
${\text{Number of moles = 0}} \cdot {\text{01125 moles}}$
Therefore, the mass of ${\text{0}} \cdot {\text{45 g}}$ sodium hydroxide has the ${\text{0}} \cdot {\text{0125 moles}}$ of sodium hydroxide.

Note:
Mole is the unit of measurement of the number of moles in the SI system. One mole contains $6 \cdot 022 \times {10^{23}}$ atoms, molecules, or ions of particles. The number of moles is used in a chemical reaction to determine how many molecules have been reacted and products formed in the reaction accordingly.