Question

Calculate the number of C, H, O atoms in 5.78 g of glucose (C6H12O6), a sugar. Enter your answers in scientific notation.

Answer 1

Number of moles of glucose = 5.78 g / 180.156 g/mol = 0.0321 mol

1 mole of glucose contains 6.023*10^23 molecules so

0.0321 mole of glucose will contain

= 0.0321 mole of glucose *(6.023*10^23 molecules / 1 mole of glucose)

= 1.93*10^22 molecules of glucose

1 molecule of glucose contains 6 carbon atoms so

1.93*10^22 molecules of glucose will contain

= 1.93*10^22 molecules of glucose *( 6 carbon atoms / 1 molecule of glucose)

= 1.16*10^23 carbon atoms

Therefore, the number of carbon atoms = 1.16*10^23

Number of hydrogen atoms = 1.93*10^22 * 12 = 2.32*10^23 hydrogen atoms

Number of oxygen atoms = 1.93*10^22 * 6 = 1.16*10^23 oxygen atoms