12.) what is the mass of 7.21 x 10^21 molecules of silver acetate (agc₂h₃o₂)? (3 points)

Explanation:

Step1: Calculate molar mass of $AgC_2H_3O_2$

The molar mass of $Ag$ is $107.87\ g/mol$, $C$ is $12.01\ g/mol$, $H$ is $1.01\ g/mol$ and $O$ is $16.00\ g/mol$. $M = 107.87+2\times12.01 + 3\times1.01+2\times16.00=166.91\ g/mol$

Step2: Find number of moles

Use Avogadro's number $N_A = 6.022\times 10^{23}\ molecules/mol$. $n=\frac{7.21\times 10^{21}\ molecules}{6.022\times 10^{23}\ molecules/mol}= 0.01197\ mol$

Step3: Calculate mass

Use the formula $m = n\times M$. $m=0.01197\ mol\times166.91\ g/mol = 2.00\ g$

Answer:

$2.00\ g$