The following models represent the structures of binary hydrides of second-row elements:
b. Draw an electron-dot structure for each hydride. For which hydride is there a problem in drawing the structure? Explain.

검증된 단계별 안내

Identify the second-row elements in the periodic table, which are: Li, Be, B, C, N, O, F, and Ne.

Recognize that binary hydrides are compounds formed between hydrogen and these elements.

Draw the Lewis electron-dot structures for each hydride:

LiH: Li has 1 valence electron, H has 1 valence electron. The structure is Li-H.

BeH2: Be has 2 valence electrons, H has 1 valence electron. The structure is H-Be-H.

BH3: B has 3 valence electrons, H has 1 valence electron. The structure is H-B-H with an additional H bonded to B.

CH4: C has 4 valence electrons, H has 1 valence electron. The structure is H-C-H with two additional H atoms bonded to C.

NH3: N has 5 valence electrons, H has 1 valence electron. The structure is H-N-H with an additional H bonded to N and a lone pair on N.

H2O: O has 6 valence electrons, H has 1 valence electron. The structure is H-O-H with two lone pairs on O.

HF: F has 7 valence electrons, H has 1 valence electron. The structure is H-F with three lone pairs on F.

NeH: Ne has 8 valence electrons, H has 1 valence electron. Ne does not typically form stable hydrides due to its full valence shell.

Explain that the problem arises with NeH, as neon is a noble gas with a complete octet, making it unlikely to form a stable hydride.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Electron-Dot Structures

Electron-dot structures, also known as Lewis structures, represent the valence electrons of atoms within a molecule. In these diagrams, dots are used to indicate the presence of valence electrons, and lines represent bonds between atoms. Understanding how to draw these structures is essential for visualizing molecular geometry and predicting reactivity.

Binary Hydrides

Binary hydrides are compounds formed between hydrogen and another element, typically from groups 1, 2, or 13 of the periodic table. The properties and bonding characteristics of these hydrides can vary significantly based on the electronegativity and atomic size of the second-row element involved. Recognizing these differences is crucial for accurately drawing their electron-dot structures.

Octet Rule and Exceptions

The octet rule states that atoms tend to form bonds in such a way that they each have eight electrons in their valence shell, achieving a stable electron configuration. However, some elements, particularly those in the second row like boron and hydrogen, can have fewer than eight electrons in their structures, leading to exceptions. Understanding these exceptions is vital for correctly identifying potential problems in drawing electron-dot structures for certain hydrides.