A) Carbon and oxygen B) Nitrogen and oxygen C) Sulphur and oxygen D) Oxygen and hydrogen
A) XY2 B) X2Y C) X2Y3 D) X3Y2
A) 8 and 2 B) 2 and 3 C) 6 and 2 D) 1 and 3
A) +7 B) +8 C) -7 D) -5
A) Sublimation B) Melting C) Crystallisation D) Evaporation
A) Argon B) Sulphur C) Chlorine D) Potassium
A) Electrons between two atoms B) Neutrons between two atoms C) Electrons from one atom to another D) Protons between two atoms
A) CO2 B) NH3 C) H2O D) NaCl
A) Transfer of electrons between atoms B) Presence of positive ions in a sea of delocalized electrons C) Formation of covalent bonds between atoms D) Sharing of electrons between atoms
A) Water B) Carbon dioxide C) Sodium chloride D) Iron
A) All of the above B) Electronegativity difference between atoms C) Atomic radius of atoms D) Electron affinity of atoms
A) Helium B) Nitrogen C) Carbon D) Oxygen
A) Weak intramolecular forces within molecules B) Strong covalent bonds between atoms C) Weak intermolecular forces between molecules D) Strong electrostatic attractions between ions
A) Hydrogen peroxide (H2O2) B) Ethanol (C2H5OH) C) Sodium chloride (NaCl) D) Methane (CH4)
A) Are closely packed together B) Have fixed positions in a lattice structure C) Have negligible volume compared to the space they occupy D) Have strong intermolecular forces of attraction
A) The density of particles within a gas B) The motion of particles within a gas C) The arrangement of particles within a gas D) The chemical reactions occurring within a gas
A) Burning of wood B) Melting of ice C) Rusting of iron D) Digestion of food
A) Volume and number of moles of a gas B) Pressure and temperature of a gas C) Pressure and volume of a gas D) Temperature and volume of a gas
A) PV = RT B) P = V/nRT C) PV = nT D) PV = nRT
A) Volume B) Pressure C) Square root of its molar mass D) Temperature
A) Density B) Atomic mass C) Number of moles D) Volume
A) Atoms in one mole of a substance B) Electrons in one atom of a substance C) Particles in one gram of a substance D) Moles in one liter of a gas
A) CO2 B) HCN C) H2O D) NH3
A) Both elements are non-metals B) Large difference in electronegativity C) High similarity in electronegativity D) Similar electron affinity values
A) Helium B) Chlorine C) Sodium D) Oxygen
A) They are responsible for the high melting and boiling points of many molecules. B) They can be polar or non-polar C) They form between atoms with similar electronegativity. D) They involve sharing electrons.
A) Covalent bonding B) Hydrogen bonding C) Dipole-dipole interactions D) London dispersion forces
A) They attract each other strongly B) They occupy a significant volume. C) They have specific shapes. D) They are constantly in motion.
A) gases expand to fill their container. B) liquids flow easily and have indefinite shapes. C) all three statements are true. D) solids are rigid and have definite shapes
A) inversely proportional to its temperature B) directly proportional to its temperature C) constant D) dependent on the container size.
A) K B) V C) R D) P
A) wood and oxygen is less than the mass of the products. B) wood and oxygen is greater than the mass of the products. C) wood and oxygen is equal to the mass of the carbon dioxide and water vapor. D) wood decreases, while the mass of the products remains constant.
A) are not needed, only the coefficients are important. B) compounds are ignored. C) reactants and products are used to convert between grams and moles. D) elements are used directly.
A) know the physical properties of all the reactants and products. B) balance the chemical equation first. C) memorize the names of all elements and compounds. D) perform complex mathematical calculations.
A) Water (H₂O) always contains hydrogen and oxygen in a 2:1 ratio by mass. B) The color of a compound can vary depending on its source. C) Carbon dioxide (CO₂) has a constant ratio of carbon to oxygen, regardless of its origin. D) All samples of table salt (NaCl) have the same ratio of sodium to chlorine.
A) Cannot be determined without additional information. B) 1:2 C) 1:3/2 D) 2:3
A) Water can decompose into hydrogen and oxygen under specific conditions. B) Hydrogen and oxygen react explosively to form water. C) Two molecules of hydrogen react with one molecule of oxygen to form two molecules of water. D) 2 grams of hydrogen react with 1 gram of oxygen to produce water.
A) all chemical reactions. B) compounds that can react with each other. C) only elements, not compounds. D) elements that can form more than one compound with another element.
A) the names of the reactants and products B) the states of matter of the reactants and products. C) the relative amounts of each molecule or atom involved in the reaction. D) the order in which the reactants combine.
A) Cannot be determined without additional information. B) 2.5 moles C) 10 moles D) 5 moles |