Chemical Bonding MCQ Trivia: Quiz!

When an atom loses electrons, it becomes positively charged. This is because electrons carry a negative charge, so when an atom loses electrons, it has more protons than electrons, resulting in a net positive charge.

Alkali metals are located in Group 1 of the periodic table, which means they have one valence electron. These metals have a tendency to lose this valence electron in order to achieve a stable electron configuration, resulting in the formation of a positively charged ion. Therefore, the charge of the ions formed by alkali metals is +1.

An ionic bond is formed when electrons are transferred. In an ionic bond, one atom donates electrons to another atom, resulting in the formation of positively and negatively charged ions. This transfer of electrons creates a strong electrostatic attraction between the ions, leading to the formation of the bond. Sharing, dividing, or losing electrons are not characteristics of an ionic bond.

An atom of oxygen becomes stable by sharing two pairs of electrons with another atom. This process is known as covalent bonding, where atoms share electrons to achieve a full outer electron shell and become stable. Oxygen has six electrons in its outer shell, so it needs to gain two more to reach stability. By sharing two pairs of electrons with another atom, oxygen can fulfill its electron requirement and become stable.

The electronic configuration of element X is 2.8.1, which means it has 2 electrons in the first shell, 8 electrons in the second shell, and 1 electron in the third shell. On the other hand, element Y has an electronic configuration of 2.6, indicating that it has 2 electrons in the first shell and 6 electrons in the second shell. In order to achieve stability, element Y needs to gain 2 electrons to complete its second shell. Therefore, the compound formed between element X and Y would be X2Y, where element Y gains 2 electrons from element X to complete its second shell.

Calcium and oxygen would form ionic compounds because calcium has a tendency to lose two electrons and become a positively charged ion (Ca2+), while oxygen has a tendency to gain two electrons and become a negatively charged ion (O2-). The attraction between these oppositely charged ions would result in the formation of an ionic compound, specifically calcium oxide (CaO).

Covalent compounds are formed by the sharing of electrons between atoms. This type of bonding results in a relatively weak force of attraction between the molecules, leading to a low melting point. In covalent compounds, the molecules are held together by intermolecular forces, which are weaker than the ionic or metallic bonds found in other types of compounds. Therefore, covalent compounds generally have lower boiling and melting points compared to ionic or metallic compounds.

Ionic compounds are able to conduct electricity in the molten and aqueous state because they consist of ions that are free to move and carry electric charge. In the solid state, the ions are held in a fixed position and are unable to move, thus preventing the flow of electric current. Furthermore, ionic compounds are generally insoluble in organic solvents and insoluble or only slightly soluble in water due to the strong attractions between the ions and the solvent molecules.

Ionic compounds can conduct electricity because the ions are able to move in liquid and molten states. In a solid state, the ions are held in fixed positions and cannot move freely. However, when the ionic compound is melted or dissolved in a liquid, the ions become free to move and carry electric charge. This movement of ions allows for the flow of electricity through the compound. The ability of the ions to move is a key factor in the conductivity of ionic compounds.

In a molecule of methane (CH4), each carbon atom forms four covalent bonds with four hydrogen atoms. A covalent bond involves the sharing of electrons between atoms. Since there are four carbon-hydrogen bonds in methane, a total of eight electrons are shared between the carbon and hydrogen atoms in the molecule. Therefore, the correct answer is 8.