Question

In the second period of the periodic table, it is possible to exceed 8 electrons in the valence shell, but an atom may not have less than 8.

a. True
b. False

Answer 1

The claim that in the second period of the periodic table it's possible to exceed 8 electrons in the valence shell while an atom cannot have less than 8 is false. The number of valence electrons can vary, typically guided by the octet rule aiming for stability with eight electrons, a trend that applies generally but has exceptions.

Step-by-step explanation:

The statement that in the second period of the periodic table it is possible to exceed 8 electrons in the valence shell but an atom may not have less than 8 is false. Atoms in the second period can have fewer than eight electrons in their valence shell. Lewis diagrams show that atoms in the second period have varying numbers of valence electrons that correspond to their position in the periodic table. As for the octet rule, it indicates that atoms tend to fill or empty their valence shell to achieve eight valence electrons, representing a stable electron configuration. However, this is a general trend and not a strict rule.

It is important to acknowledge that atoms with fewer than four valence electrons may lose them to form positively charged cations, resulting in a lower shell becoming the valence shell that may have an octet. On the other hand, expanded octets occur in elements in the third period and beyond due to the presence of empty d orbitals in the same shell, allowing these elements to accommodate more than eight valence electrons.

Answer 2

b. False. Atoms in the second period of the periodic table can have a maximum of 8 electrons in the valence shell, adhering to the octet rule for stability. The false statement incorrectly suggests the possibility of exceeding 8 electrons in the valence shell in the second period, which contradicts the known electron capacity of the relevant sublevels.

Step-by-step explanation:

The statement is false because in the second period of the periodic table, the maximum number of electrons that can occupy the valence shell is 8. This is due to the fact that the second period elements, specifically those in the s and p sublevels, follow the octet rule. The s sublevel can hold a maximum of 2 electrons, and the p sublevel can hold a maximum of 6 electrons. Therefore, the total number of electrons that can occupy the valence shell in the second period is 2 + 6 = 8.

The octet rule states that atoms tend to gain, lose, or share electrons in order to achieve a full set of 8 electrons in their valence shell, making them more stable. This stability is observed in noble gases, which have a full set of 8 electrons in their outermost shell. Elements in the second period strive to attain this electron configuration to achieve stability.

In summary, while it is not possible for an atom in the second period to exceed 8 electrons in the valence shell, it is crucial to reach the octet configuration for enhanced stability, aligning with the principles of the octet rule in chemical bonding and reactivity.