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• Sickle cell anaemia is a genetic disorder in which a mutation in the DNA changes the amino acid in the protein, affecting its structure.
• As a result, hemogiobin's structure changes from round to sickle cell, destroying its ability to carry oxygen.
• Patients with sickle cell anaemia who take hydroxyurea on a daily basis report less pain, fewer events where blood vessels are obstructed by sickle red blood cells, and increased blood flow.

Molar mass is the mass of 1 mole of substance. Molar mass of hydroxyurea is:

The chemical formula for hydroxyurea is ${\mathrm{CH}}_4{\mathrm{N}}_2{\mathrm{O}}_2$. So it contains 1 carbon atom, 4 hydrogen atoms, 2 nitrogen atoms and 2 oxygen atoms.

• Atomic mass of hydrogen atom is $1.007$
• Atomic mass of carbon atom is $12.0107$
• Atomic mass of nitrogen atom is $\mathbf{14}\mathbf{.}\mathbf{006}$
• Atomic mass of oxygen atom is$15.9994$

For calculating the molar mass multiply how many of each atoms by the mass of that atom.

Hydroxyurea $-{\mathrm{CH}}_4{\mathrm{N}}_2{\mathrm{O}}_2$

• 1 carbon atom $-1×12.0107=12.0107\mathrm{g}/\mathrm{mol}$ (molar mass constant)
• 4 hydrogen atoms $-4×1.007=4.028\mathrm{g}/\mathrm{mol}$
• 2 nitrogen atoms $-2×14.006=28.012\mathrm{g}/\mathrm{mol}$
• 2 oxygen atoms$-2×15.9994=31.9988\mathrm{g}/\mathrm{mol}$

Now add the products together

The molar mass of hydroxyurea is $-76.0495\mathrm{g}/\mathrm{mol}$