A) A substance made up of atoms with the same number of protons B) A substance made from two or more elements chemically combined C) A substance that can always be separated physically D) A mixture of different substances
A) An atom B) A mixture C) A compound D) A molecule of water
A) C B) Co C) Ca D) Cr
A) The first letter is always capitalised B) Chemical symbols are written only in lowercase C) All chemical symbols contain two capital letters D) The second letter is always capitalised
A) nA B) Na C) NA D) na
A) The number of neutrons in its atoms B) The physical state of the element C) The number of protons in its atoms D) The number of molecules present
A) Oxygen B) Argon C) Helium D) Neon
A) Cl B) Cl? C) C?l D) Cl?
A) In order of melting point B) In alphabetical order C) In order of atomic number D) In order of density
A) Carbon dioxide B) Sodium chloride C) Carbon D) Water
A) A single atom B) A substance containing two or more different elements chemically combined C) A substance containing only one type of atom D) A physical mixture of substances
A) A fixed ratio B) A ratio determined by the size of the sample C) A changing ratio D) Any ratio
A) The mass of the whole sample only B) The types and relative numbers of atoms present C) The colour of the compound D) The temperature at which it forms
A) HO? B) H?O? C) OH D) H?O
A) NH? B) NO? C) NH? D) N?H?
A) Ionic compound B) Mixture C) Elemental molecule D) Covalent compound
A) Metallic element B) Covalent compound C) Ionic compound D) Alloy
A) Two B) Four C) Three D) One
A) Carbon dioxide B) Carbon trioxide C) Carbon monoxide D) Cobalt dioxide
A) It contains only one element B) Its components retain all their original properties and can be separated by filtering C) Its elements are chemically combined and cannot be separated by physical methods D) Its elements are mixed in any proportion
A) Below the arrow B) On the right-hand side C) On the left-hand side D) Above the arrow
A) Reactants B) Mixtures C) Catalysts D) Products
A) Is equal to in mass only B) Dissolves in C) Produces or forms D) Is heated by
A) The left-hand side B) Neither side C) Both sides always D) The right-hand side
A) Solution B) Solid C) Salt D) Steam
A) A pure liquid B) Aqueous solution C) A solid D) A gas
A) (l) B) (g) C) (aq) D) (s)
A) To make the equation shorter B) To make the products heavier than the reactants C) To show the same number of each type of atom on both sides D) To show that atoms disappear during reactions
A) Change of state B) Conservation of temperature C) Conservation of mass D) Formation of mixtures
A) 2Al + 3CuO ? Al?O? + 3Cu B) Al + 3CuO ? Al?O? + 3Cu C) Al + CuO ? Al?O? + Cu D) 2Al + CuO ? Al?O? + Cu
A) Definite proportions B) Multiple proportions C) Conservation of mass D) Conservation of energy
A) Addition reaction B) Combustion reaction C) Decomposition reaction D) Neutralization reaction
A) 3H2SO4 + 2Al(OH)_3 --> Al2(SO4)_3 + 8H2O B) H2SO4 + Al(OH)_3 --> Al2(SO4)_3 + 2H2O C) H2SO4 + Al(OH)_3 --> Al2(SO4)_3 + H2O D) 3H2SO4 + 2Al(OH)_3 --> Al2(SO4)_3 + 6H2O
A) 4;2;1 B) 1;2;4 C) 4;1;2 D) 2;4;1
A) 2:15;18;16 B) 2;25;16;18 C) 18;16;25;2 D) 25;16;2;18
A) 7;4;6;2 B) 4;6;7;2 C) 7;4;2;6 D) 2;7;4;6
A) 4;3;5;1 B) 3;5;1;4 C) 5;1;3;4 D) 1;5;3;4
A) 1;2;2;1;1 B) 2;2;1;1;1 C) 2;2;1;2;1 D) 2;1;2;1;1
A) 2;2;3;3 B) 2;3;2;3 C) 3;3;3;2 D) 3;3;2;3
A) 4;3;3;6 B) 4;3;6;2 C) 4;3;2;6 D) 6;2;3;4
A) 2;3;4 B) 4;3;2 C) 4;2;3 D) 3;2;4
A) 4,;8;2;11 B) 4;11;2;8 C) 11;4;2;8 D) 4;8;2;11
A) CxHy + x+y/2O2 --> xCO2 + y/4H2O B) CxHy + x+y/4O2 --> xCO2 + y/2H2O C) CxHy + y/4O2 --> xCO2 + y/2H2O D) CxHy + x+y/4O2 --> xCO + y/2H2O |