1 Nadia is contrasting ionic and covalent compounds. She learns that covalent compounds are usually poor conductors of electricity. Why are covalent compounds poor conductors? A Because they have free electrons B Because they do not have free ions or electrons C Because they have ionic bonds D Because they have metallic bonds
2 Which bond is formed due to electrostatic attraction? A Covalent bond B Ionic bond C Hydrogen bond D Single bond
3 Waseem is studying the empirical formula of a compound. He analyzes a compound and finds its mass composition: 32% sulfur and 48% oxygen. What is the empirical formula? (S=32, O=16) A SO B SO2 C SO3 D S2O3
4 Victor is balancing the equation: N2 + H2 → NH3. What is the correct balanced equation? A N2 + 3H2 → 2NH3 B N2 + H2 → NH3 C 2N2 + H2 → 2NH3 D N2 + 2H2 → NH3
6 Oliver is balancing a chemical equation. He has the equation: H2 + O2 → H2O. What is the coefficient of water when the equation is balanced? A 1 B 2 C 3 D 4
7 Qasim is studying the nature of bonding and structure. He learns that the structure of a substance determines its properties. Which type of structure does sodium chloride have? A Giant covalent structure B Giant ionic lattice C Simple molecular structure D Metallic structure
8 Qasim is learning about the uses of graphite. He understands that graphite is used as a lubricant. Why is graphite a good lubricant? A Because it is very hard B Because layers can slide over each other easily C Because it is a good conductor of electricity D Because it is chemically inert
9 Which bond explains the high boiling point of water? A Covalent bond B Ionic bond C Hydrogen bonding D Metallic bond
11 Which of the following is essential for writing empirical formula? A Atomic numbers B Percentage composition C Molecular mass D Density
12 Nora is calculating the formula mass of CaCO3. She knows Ca=40, C=12, O=16. What is the formula mass? A 100 g/mol B 84 g/mol C 112 g/mol D 96 g/mol
13 Quinn is studying molecular and structural formulas. He knows that the molecular formula shows the actual number of atoms, while the structural formula shows how atoms are arranged. Which formula shows the arrangement of atoms? A Molecular formula B Empirical formula C Structural formula D Formula mass
15 Bilal is studying the duplet rule. He learns that it applies to certain elements. For which element does the duplet rule apply for stability? A Oxygen B Chlorine C Hydrogen D Sodium
16 Xia is learning about binary ionic compounds. She wants to write the formula for calcium fluoride. What is the correct formula? A CaF B CaF2 C Ca2F D CaF3
17 Paula is studying the structure of graphite. She learns that graphite has a layered structure. What is the arrangement of carbon atoms in graphite? A Three-dimensional network B Hexagonal layers with weak forces between layers C Tetrahedral arrangement D Cubic structure
18 Chloe is calculating the molecular mass of glucose (C6H12O6). She knows the atomic masses: C=12, H=1, O=16. What is the molecular mass of glucose? A 180 g/mol B 150 g/mol C 200 g/mol D 120 g/mol
19 Mohamed is learning about the condition of electricity in ionic compounds. He knows that ionic compounds conduct electricity in certain states. In which state do ionic compounds conduct electricity? A Solid state B Molten or aqueous state C Gaseous state D Vapor state
20 David is studying an ionic compound, NaCl. He wants to calculate the formula mass. He knows Na=23 and Cl=35.5. What is the formula mass of NaCl? A 58.5 g/mol B 60.5 g/mol C 55.5 g/mol D 50.0 g/mol
22 Stoichiometry is the study of: A Atomic structure B Chemical calculations C Chemical bonding D States of matter
23 The sharing of one pair of electrons forms a: A Double bond B Triple bond C Single bond D Ionic bond
25 George is learning about intermolecular forces. He understands that dipole-dipole forces are stronger than London dispersion forces. Which of the following substances has dipole-dipole forces as the main intermolecular force? A F2 B HCl C CH4 D CCl4