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