Question

calculate the molar concentration a solution containing 7.868e+1 grams of nacl in 0.850 liters of water. remember that the molar mass is the mass (in grams) of one mole of a substance.

Explanation:

Step1: Calculate the molar mass of NaCl

The molar mass of \(Na\) is \(22.99\space g/mol\) and of \(Cl\) is \(35.45\space g/mol\). So, molar mass of \(NaCl\), \(M = 22.99+35.45=58.44\space g/mol\)

Step2: Calculate the number of moles of NaCl

Using the formula \(n=\frac{m}{M}\), where \(m = 7.868\times10^{1}\space g\) (i.e., \(78.68\space g\)) and \(M = 58.44\space g/mol\). Then \(n=\frac{78.68}{58.44}\approx1.346\space mol\)

Step3: Calculate the molar concentration

Using the formula \(C=\frac{n}{V}\), where \(n = 1.346\space mol\) and \(V=0.850\space L\). Then \(C=\frac{1.346}{0.850}\approx1.58\space mol/L\)

Answer:

\(1.58\space mol/L\)