Grade 11 Chemistry diagnostic

16 questions on general chemistry, chemical reactions, acids, bases & ph, analytical chemistry, physical chemistry, organic chemistry and biochemistry, plus 2 from Grade 10. Answer what you can, then check your answers to see which topics are secure and what to practise next.

16 questions7 topicsAbout 20 minutesSet 1 of 5

Skip a question if you do not know the answer. It is better than guessing, because it shows what to practise.

1General chemistryA model sample has mass 155 g and stated molar mass 20 g/mol. Find its amount. Round to 3 decimal places if needed. Answer in mol.

Your answermol

2General chemistryA sample contains 3.5 mol and has stated molar mass 66 g/mol. Find its mass. Round to 3 decimal places if needed. Answer in g.

Your answerg

3Chemical reactionsBalance this equation using the smallest whole-number coefficients: __ KClO₃ → __ KCl + __ O₂. What is the sum of all the coefficients?

Your answer

4Chemical reactionsIn a sealed container, a 14.3 g sample of a compound decomposes completely into 12.2 g of a gas and one solid product. What is the mass of the solid?

Your answerg

5Acids, bases & pHSolution X has pH 3 and solution Y has pH 2. Which is more basic?

A. the solution with pH 2B. the solution with pH 3

6Acids, bases & pHSolution X has pH 1 and solution Y has pH 8. Which is more acidic?

A. the solution with pH 1B. the solution with pH 8

7Analytical chemistryAn aqueous solution has concentration 0.9 mol/L. A model aliquot has volume 213 mL. Find the solute amount. Round to 3 decimal places if needed. Answer in mol.

Your answermol

8Analytical chemistryA model solution contains 1.3 mol in a final volume of 0.98 L. Find its molar concentration. Round to 3 decimal places if needed. Answer in mol/L.

Your answermol/L

9Physical chemistryUse PV = nRT and R = 8.314 kPa·L/(mol·K). Find the ideal-gas volume for 1.4 mol at 281 K and 126 kPa. Round to 3 decimal places if needed. Answer in L.

Your answerL

10Physical chemistryFor one reaction as written, a bond model requires 985 kJ/mol to break bonds and releases 713 kJ/mol on forming bonds. Estimate ΔH. Round to 3 decimal places if needed. Answer in kJ/mol.

Your answerkJ/mol

11Organic chemistryA hydrocarbon molecule contains 7 carbon atoms. In a complete-combustion model, all its carbon forms CO₂. How many moles of CO₂ come from 3.4 mol hydrocarbon? Round to 3 decimal places if needed. Answer in mol.

Your answermol

12Organic chemistryIgnoring end groups in a supplied model, a polymer chain has 500 repeat units, each contributing 28 g/mol to the chain molar mass. Estimate that mass. Round to 3 decimal places if needed. Answer in g/mol.

Your answerg/mol

13BiochemistryA simple unbranched, noncyclic peptide contains 68 amino-acid residues. How many peptide links connect adjacent residues? Round to 3 decimal places if needed.

Your answer

14BiochemistryAt fixed temperature, does an enzyme make equilibrium permanently favor more product?

A. Only by consuming all atoms.B. Yes, every enzyme changes K.C. No; it can accelerate approach to equilibrium.

From Grade 10

These questions check skills from the grade below, so gaps can be spotted early.

15General chemistry (Grade 10)What must two isotopes of one element share?

A. Their proton count.B. Their mass number.C. Their neutron count.

16General chemistry (Grade 10)In 3CO₂, how many oxygen atoms are represented?

Your answer