Test: Stoichiometry - Year 3 MCQ

Total carbon = 10 x 12 = 120. Total hydrogen = 15 x 1 = 15. Total nitrogen = 14 x 1 = 14. Total oxygen = 16 x 1 = 16. Add together = 165 amu

Remember, be methodical. There are 13 hydrogen atoms in the molecule so they contribute 13 x 1 =13 amu to the total. To work this out as a percentage:13 /135 = 0.096 x 100 = 9.6%

Divide the % by RAM for each individual element. Divide those answers by the smallest which will give you your final ratios

The mole ratio is determined by dividing the coefficients of reactants and products in a balanced chemical equation.

40 + 2 x 35.5 + 2 x 16 = 143 amu

Stoichiometry is the calculation of quantities of substances involved in chemical reactions based on balanced equations.

Reactants are the substances present at the start of a chemical reaction that undergo change to form products.

A balanced chemical equation ensures the conservation of atoms of each element in the reactants and products.