Question

the table gives the quantities, in moles (mol), of atoms in one mole of glycerol and the approximate mass, in grams per mole (g/mol), of those atoms. to the nearest percent, what percent of the mass of the mole of glycerol is from oxygen atoms? (round to the nearest percent. ignore the % symbol when entering your answer. for example, if the answer is 11.2%, enter 11.)

Explanation:

Step1: Calculate the mass of each atom

• Carbon:

The formula for mass is \(m = n\times M\) (where \(n\) is the amount of substance in mol and \(M\) is the molar mass). For carbon, \(n = 3\space mol\) and \(M=12\space g/mol\). So, \(m_{C}=3\times12 = 36\space g\)

• Hydrogen:

For hydrogen, \(n = 8\space mol\) and \(M = 1\space g/mol\). So, \(m_{H}=8\times1=8\space g\)

• Oxygen:

For oxygen, \(n = 3\space mol\) and \(M = 16\space g/mol\). So, \(m_{O}=3\times16=48\space g\)

Step2: Calculate the total mass of the molecule

The total mass of the molecule \(m_{total}=m_{C}+m_{H}+m_{O}\)
\(m_{total}=36 + 8+48=92\space g\)

Step3: Calculate the percentage of oxygen mass

The percentage of oxygen mass \(P=\frac{m_{O}}{m_{total}}\times100\%\)
\(P=\frac{48}{92}\times 100\%=\frac{4800}{92}\%\approx52.17\%\)

Answer:

52