MDCAT Chemistry MCQs

Moles equal particles divided by Avogadro's number.
1.2044×10^24 ÷ 6.022×10^23 = 2 mol.

Carbon contributes about 12 and two oxygens contribute 32.
The total molar mass is about 44 g/mol.

Oxygen contributes 16 of the 18 g/mol formula mass.
16/18×100 ≈ 88.9%.

The coefficients of H2 and H2O are equal.
Thus 4 mol H2 produce 4 mol H2O.

The mole ratio H2:NH3 is 3:2.
6 mol H2×2/3 = 4 mol NH3.

Percent yield is actual divided by theoretical times 100.
8/10×100 = 80%.

Stoichiometry uses balanced equations to relate amounts.
It supports mass, mole, particle, and gas calculations.

Moles equal mass divided by molar mass.
18 g ÷ 18 g/mol = 1 mol.

Balancing follows conservation of atoms and mass.
Coefficients change amounts, not chemical formulas.

Chemistry examines what matter is made of and how it behaves.
It also studies energy changes accompanying chemical processes.

Equation coefficients give stoichiometric ratios.
They may be interpreted as molecule or mole ratios.

Matter includes solids, liquids, gases, and plasma.
It is composed of atoms, molecules, or ions.