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