861 past contests
Topic 3 · True or false: formate (cho2-) is a stronger base than acetate (c2h3o2-)
Topic 3 · True or false: hypochlorite (clo-) is a stronger base than chloride (cl-)
Topic 3 · True or false: a weak acid's dissociation constant is higher at lower concentration
Topic 3 · True or false: a weak acid's dissociation constant is independent of temperature at constant concentration
Topic 3 · True or false: a weak acid's dissociation constant is lower at lower concentration
Topic 19 · Total atoms in a molecular formula scaled up from an empirical formula via a known atom count
Topic 9 · Sum of stoichiometric coefficients in balanced al(oh)3+h2so4→al2(so4)3+h2o
Topic 20 · Volume of solution needed to dissolve a mass of sodium carbonate to a target concentration
Topic 1 · Mass of water produced from combusting 8.80g of methane
Topic 1 · Mass of co2 produced from combusting 16.8g of ethene
Topic 1 · Mass of co produced from incomplete combustion of 20.8g methane
Topic 38 · Three major products of concentrated nacl(aq) electrolysis: chlorine gas, sodium hydroxide and hydrogen gas
Topic 14 · Riddle: sulphur, a nonmetal by-product of fossil fuel refining with several allotropes
Topic 26 · True or false: c4h8 has 4-bromobutane as an isomer
Topic 26 · True or false: c4h8 has only two isomers (but-1-ene and but-2-ene)
Topic 26 · True or false: c4h8 has 2-bromo-2-methylbutane as an isomer
Topic 22 · True or false: 2-chloropropanoic acid is a stronger acid than propanoic acid
Topic 22 · True or false: ethanoic acid is a stronger acid than propanoic acid
Topic 22 · True or false: methanoic acid is a stronger acid than ethanoic acid
Topic 14 · True or false: zno is yellow when hot and white when cold