Question

the percent by mass of barium in ba(cn)2 is __%. use the references to access important values if needed. 9 more group attempts remaining. submit answer retry entire group

Explanation:

Step1: Determine molar masses

The molar mass of Ba(CN)$_2$:
The molar mass of Ba ($M_{Ba}$) is approximately 137.33 g/mol, the molar mass of C ($M_{C}$) is 12.01 g/mol, and the molar mass of N ($M_{N}$) is 14.01 g/mol. For Ba(CN)$_2$, $M = M_{Ba}+2\times(M_{C}+M_{N})=137.33 + 2\times(12.01+14.01)=137.33+2\times26.02=137.33 + 52.04=189.37$ g/mol.

Step2: Calculate percent - by - mass of Ba

The percent - by - mass of Ba in Ba(CN)$_2$ is calculated using the formula $\text{Percent by mass}=\frac{\text{Mass of Ba}}{\text{Mass of Ba(CN)}_2}\times100\%$. Substituting the values, we get $\frac{137.33}{189.37}\times100\%\approx72.52\%$.

Answer:

72.52