# How many grams of NaCl equal a mole of NaCI?

##### 1 Answer

#### Explanation:

The problem essentially wants you to find the **molar mass** of sodium chloride, *molar mass* of an ionic compound gives you the mass of **one mole** of formula units of that compound.

Now, as given by the compound's chemical formula, one formula unit of sodium chloride contains

,one sodium cation#1 xx "Na"^(+)# ,one chloride anion#1 xx "Cl"^(-)#

This means that the mass of **one mole of formula units** will be equal to the sum of the mass of **one mole** of sodium cations and the mass of **one mole** of chloride anions.

Since the mass of an ion is basically *the same* as the mass of the **neutral atom**, you can say that the **molar mass** of sodium chloride will be equal to the sum of the **molar mass** of sodium, **molar mass** of chlorine,

As given in the Periodic Table of Elements, these are equal to

#M_("M Na") = "22.98977 g mol"^(-1)#

#M_("MCl") = "35.4527 g mol"^(-1)#

You thus have

#M_("M NaCl") = "22.98977 g mol"^(-1) + "35.4527 g mol"^(-1)#

#M_("M NaCl") = "58.44247 g mol"^(-1)#

This means that the mass of **one mole** of sodium chloride is equal to

#color(green)(|bar(ul(color(white)(a/a)color(black)(m_("NaCl / 1 mole") = "58.44247 g")color(white)(a/a)|)))#