Question

1. how many grams of sodium chloride are present in 2.39 moles of this compound? grams. 2. how many moles of sodium chloride are present in 2.25 grams of this compound? moles.

Explanation:

Step1: Determine molar - mass of NaCl

The molar mass of Na (sodium) is approximately 22.99 g/mol and Cl (chlorine) is approximately 35.45 g/mol. So, the molar mass of NaCl, $M = 22.99+35.45=58.44$ g/mol.

Step2: Calculate mass for 2.39 moles of NaCl

We use the formula $m = n\times M$, where $n$ is the number of moles and $M$ is the molar mass. For $n = 2.39$ moles and $M = 58.44$ g/mol, $m=2.39\times58.44 = 139.6716$ g.

Step3: Calculate moles for 2.25 g of NaCl

We use the formula $n=\frac{m}{M}$. Given $m = 2.25$ g and $M = 58.44$ g/mol, $n=\frac{2.25}{58.44}\approx0.0385$ moles.

Answer:

1. 139.6716
2. 0.0385