Morphine is a well known pain killer but is highly addictive. The lethal dose of morphine varies from person to person based on their body weight and other factors but is somewhere near 70 mg. Calculate the number of millimoles of carbon atoms in 71.891 mg sample of morphine. Report your answer to the third decimal place.

0.252 milimoles

Explanation:

To convert mass of a substance to moles it is necessary to use the molar mass of the substance.

The formula of morphine is C₁₇H₁₉NO₃, thus, its molar mass is:

C: 17*12.01g/mol = 204.17g/mol

H: 19*1.01g/mol = 19.19g/mol

N: 1*14g/mol = 14g/mol

O: 3*16g/mol = 48g/mol.

204.17 + 19.19 + 14 + 16 = 285.36g/mol

Thus, moles of 71.891 mg = 0.071891g:

0.071891g × (1mol / 285.36g) = 2.5193x10⁻⁴ moles

As 1 mole = 1000 milimoles:

2.5193x10⁻⁴ moles = 0.252 milimoles