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First-year chemistry: a study plan that works

A study plan for first-year general chemistry: stoichiometry, equilibrium and acids and bases, with worked examples, unit tracking and a weekly routine.

By the StudyBrix team · · 5 min read · For First-year university students and Grade 12 chemistry students

In short

  • General chemistry exams are mostly problems. Spend most of your time solving them with the answer hidden, not rereading notes.
  • Master the mole first: nearly every later topic (stoichiometry, gases, equilibrium, pH) is mole arithmetic in disguise.
  • Write units on every number and cancel them; units catch most setup mistakes before you calculate.
  • Learn a few reliable methods, like the ICE table and the small-x check, and practise them on mixed problems.

What first-year general chemistry usually covers

The order differs between schools. At UBC Vancouver, for instance, first-term chemistry focuses on structure and bonding (with a version that includes equilibrium for students without Chemistry 12), and a second-term course covers thermodynamics, kinetics and organic chemistry. Most first-year sequences in Canada include the same core:

  • Atoms, the mole, formulas and balancing equations
  • Stoichiometry, limiting reactants and percent yield
  • Gases and solutions (molarity, dilution)
  • Thermochemistry and, often, thermodynamics
  • Chemical equilibrium and Le Chatelier's principle
  • Acids, bases, pH, buffers and titrations
  • Bonding, molecular shape and intermolecular forces

Use your course syllabus as the map. If Chemistry 12 feels distant, the chemistry readiness deck and the Grade 12 chemistry diagnostic are quick ways to find gaps before they slow you down.

A weekly routine for general chemistry

WhenWhat to doTime
After each lectureMake 5 to 10 flashcards: definitions, equations, constants, the first step of each method15 min
Same daySolve 4 to 6 textbook problems from that lecture, answers hidden45 min
Every dayFlashcard review10 min
Before labRead the procedure, write out the calculations you will need30 to 45 min
WeekendMixed set of 8 problems from all units so far1 h
WeekendList what you could not do; bring it to office hours or tutorial10 min

Flashcards suit chemistry better than most science courses, because there is a lot to hold in your head: polyatomic ions, strong acids and bases, solubility rules, constants. Our decks for General chemistry I and General chemistry II cover these, and spaced repetition flashcards explains the review schedule.

Use units on every line

Dimensional analysis is the single best habit in general chemistry. Write the unit beside every number, multiply by conversion factors written as fractions, and check that the units cancel to what the question asks for. If you end up with g²/mol, the setup is wrong and you know it before the exam does.

Dilution with units

How many mL of 6.0 mol/L HCl do you need to make 250 mL of 0.250 mol/L HCl?

M1V1 = M2V2, so V1 = (0.250 mol/L × 250 mL) / 6.0 mol/L.

mol/L cancels, leaving mL. V1 = 10.4 mL (about 10 mL to two significant figures).

A few constants are worth knowing cold. The Avogadro constant is exactly 6.022 140 76 × 10^23 per mole; it has been a fixed defining constant of the SI since the revision adopted in 2018 (in force from May 2019). Your course will also use molar masses from the periodic table it provides; use those values, since tables round slightly differently.

Keep extra digits through the middle of a calculation and round only at the end. Rounding at every step can shift the last digit of your final answer, and on a multiple-choice exam that is often the difference between two options.

Stoichiometry: the worked example to master

Almost every stoichiometry question follows one path: grams to moles, moles to moles using the balanced equation, moles back to grams. Limiting reactant questions add one step: work out which reactant runs out first.

Limiting reactant

Propane burns: C3H8 + 5 O2 -> 3 CO2 + 4 H2O. You have 10.0 g of propane and 32.0 g of O2. What mass of CO2 forms?

Moles: propane 10.0 g ÷ 44.10 g/mol = 0.2268 mol. O2 32.0 g ÷ 32.00 g/mol = 1.000 mol.

O2 needed for all the propane: 0.2268 × 5 = 1.134 mol. Only 1.000 mol is available, so O2 is limiting.

CO2 from O2: 1.000 mol O2 × (3 mol CO2 / 5 mol O2) = 0.6000 mol CO2.

Mass: 0.6000 mol × 44.01 g/mol = 26.4 g CO2.

Equilibrium: use an ICE table every time

For equilibrium problems, set up an ICE table (Initial, Change, Equilibrium) in mol/L, write the expression for K, and solve. Doing it the same way every time stops sign errors.

ICE table

H2(g) + I2(g) <=> 2 HI(g). Take Kc = 50.0 at the temperature of the experiment. Start with 1.00 mol/L each of H2 and I2 and no HI. Find the equilibrium concentrations.

I: [H2] = 1.00, [I2] = 1.00, [HI] = 0. C: -x, -x, +2x. E: 1.00 - x, 1.00 - x, 2x.

Kc = (2x)^2 / (1.00 - x)^2 = 50.0. Take the square root: 2x / (1.00 - x) = 7.071.

Solve: x = 7.071 / 9.071 = 0.780.

At equilibrium: [HI] = 1.56 mol/L, [H2] = [I2] = 0.220 mol/L. Check: 1.559^2 / 0.2205^2 = 50.0.

Acids and bases: pH problems step by step

pH is the negative base-10 log of the hydronium ion concentration. At 25 °C, Kw = 1.0 × 10^-14, so pH + pOH = 14.00. For pH, the number of decimal places in the answer equals the number of significant figures in the concentration.

Strong acid

0.0050 mol/L HCl is a strong acid, so [H3O+] = 0.0050 mol/L.

pH = -log(0.0050) = 2.30 (two significant figures, two decimal places).

Weak acid

Find the pH of 0.10 mol/L acetic acid, Ka = 1.8 × 10^-5.

Ka = x^2 / (0.10 - x). Assume x is small: x^2 = 1.8 × 10^-6, x = 1.34 × 10^-3 mol/L.

Check the assumption: 1.34 × 10^-3 is 1.3% of 0.10, under 5%, so it holds.

pH = -log(1.34 × 10^-3) = 2.87.

The most common errors: treating a weak acid as if it fully ionizes (which would give pH 1.00 here), forgetting to check the 5% assumption, and mixing up pH and pOH for bases. For more practice, see the acids and bases guide and the equilibrium guide.

The two weeks before a chemistry exam

  1. List every problem type on the syllabus (for example: limiting reactant, dilution, ICE table, weak acid pH, buffer pH).
  2. Do two problems of each type without notes. Mark the ones you miss.
  3. Rework the missed types until you can do them cold, then mix them with the rest.
  4. Write one full past exam or practice exam under time, with only the data sheet your course allows.
  5. In the last two days, review flashcards and your mistake list. Sleep a normal night.

Our final exam study plan shows how to fit this alongside other courses.

Sources

  1. OpenStax Chemistry 2e, section 14.2: pH and pOH
  2. OpenStax Chemistry 2e, section 14.1: Brønsted-Lowry acids and bases (Kw)
  3. BIPM: SI defining constants
  4. UBC Vancouver Academic Calendar: Chemistry course descriptions

General information for study and teaching, not professional, legal or admissions advice. Rules and requirements change: check the official pages linked above. Found a mistake? Tell us and we will correct it. How we write: editorial policy.

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