Calculate the percent by mass of C in pentaerythritol (C (CH2OH) 4)

Formula for pentaerythritol = C5H12O4

mass of pentaerythritol = 5 (12) + 12 (1) + 4 (16)

= 60 + 12 + 64

= 138 amu

mass of C = 12 amu

% of C in C5H12O4 = [{5 (12) } / 138 ] * 100

= (60 / 138) * 100 = 43.47%