2 Which of the following is a property of covalent compounds? A They are generally soluble in water B They have high melting and boiling points C They conduct electricity in aqueous solution D They are usually poor conductors of electricity
3 Which of the following is formed when a metal atom loses electrons and a non-metal atom gains electrons? A Covalent bond B Ionic bond C Metallic bond D Hydrogen bond
4 A molecule formed by the sharing of electrons between two identical atoms is called: A Heteronuclear molecule B Homonuclear molecule C Polar molecule D Ionic molecule
5 Which of the following atoms will most likely form a cation? A Chlorine B Oxygen C Sodium D Fluorine
6 Which of the following is a property of ionic compounds? A They are generally gases at room temperature. B They have low melting and boiling points. C They conduct electricity in molten state. D They are insoluble in water.
7 The duplet rule is applicable to atoms that need how many electrons in their outermost shell to become stable? A 2 B 8 C 18 D 32
9 Ionic compounds conduct electricity in molten state because: A They contain free electrons B They contain free ions C They contain free protons D They contain free neutrons
10 Which of the following statements about polar covalent bonds is correct? A Electrons are shared equally between atoms B Electrons are transferred completely from one atom to another C Electrons are shared unequally due to difference in electronegativity D They occur only between identical atoms
11 How many electrons are present in the valence shell of a chlorine atom (atomic number 17)? A 1 B 3 C 5 D 7
14 Which of the following is the primary reason why atoms form chemical bonds? A To increase their atomic number B To achieve a stable electron configuration C To become radioactive D To increase their mass number
15 Covalent bonds are formed by: A Transfer of electrons B Sharing of electrons C Gain of electrons D Loss of electrons
16 Which of the following statements best explains why atoms form chemical bonds? A To increase the number of protons in the nucleus B To attain a stable electronic configuration with a complete valence shell C To decrease the overall energy of the nucleus D To increase the number of shells in the atom
17 Which type of bond is formed by the transfer of electrons from a metal to a non-metal? A Covalent bond B Ionic bond C Metallic bond D Hydrogen bond
18 The bond formed by sharing of one pair of electrons between two atoms is called: A Single covalent bond B Double covalent bond C Triple covalent bond D Ionic bond
19 Which of the following is an example of a molecule with a triple covalent bond? A H2 B O2 C N2 D Cl2
20 Why do ionic compounds have high melting and boiling points? A They have weak intermolecular forces. B They consist of molecules. C They have strong electrostatic forces between ions. D They share electrons.
22 Which of the following compounds conducts electricity when dissolved in water? A Sugar (C₁₂H₂₂O₁₁) B Ethanol (C₂H₅OH) C Potassium iodide (KI) D Carbon dioxide (CO₂)
23 The number of electrons in the valence shell of an atom can be determined from the periodic table by: A its atomic mass B its group number C its period number D its atomic radius
24 Which of the following properties is typical of ionic compounds? A Low melting and boiling points B Poor electrical conductivity in molten state C High melting and boiling points D Exist as gases at room temperature
25 According to the octet rule, atoms tend to gain, lose, or share electrons to achieve: A 2 electrons in the outermost shell B 8 electrons in the outermost shell C 8 electrons in the nucleus D 18 electrons in the valence shell