Predict the shape and polarity of each of the following molecules, which have polar covalent bonds:
a. A central atom with three identical bonded atoms and one lone pair.

검증된 단계별 안내

Determine the electron group geometry around the central atom. Since there are three bonded atoms and one lone pair, the total number of electron groups is 4. This corresponds to a tetrahedral electron group geometry.

Identify the molecular shape. With one lone pair and three bonded atoms, the molecular shape is trigonal pyramidal. Lone pairs repel bonded atoms more strongly, causing the bonded atoms to be pushed closer together.

Assess the bond polarity. Since the bonds are described as polar covalent, the bonded atoms have different electronegativities, resulting in partial charges on the bonds.

Evaluate the overall molecular polarity. Due to the asymmetrical shape (trigonal pyramidal), the dipole moments of the polar bonds do not cancel out, making the molecule polar.

Summarize: The molecule has a trigonal pyramidal shape and is polar due to its asymmetrical geometry and the presence of polar covalent bonds.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

도움이 되었나요?

주요 개념

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

Molecular Geometry

Molecular geometry refers to the three-dimensional arrangement of atoms in a molecule. It is determined by the number of bonding pairs and lone pairs of electrons around the central atom, which influences the shape of the molecule. For example, a central atom with three identical bonded atoms and one lone pair adopts a trigonal pyramidal shape due to the repulsion between the lone pair and the bonded atoms.

Polarity of Molecules

Polarity in molecules arises from the distribution of electrical charge, which is influenced by the presence of polar covalent bonds. A molecule is considered polar if it has a net dipole moment, resulting from an uneven distribution of electron density. In the case of a trigonal pyramidal molecule, the lone pair creates an area of negative charge, leading to a polar molecule with a distinct positive and negative end.

VSEPR Theory

Valence Shell Electron Pair Repulsion (VSEPR) theory is a model used to predict the geometry of molecules based on the repulsion between electron pairs surrounding a central atom. According to VSEPR, electron pairs, whether bonding or lone pairs, will arrange themselves to minimize repulsion, thus determining the molecular shape. This theory helps explain why a central atom with three bonded atoms and one lone pair forms a trigonal pyramidal shape.

Predict the shape and polarity of each of the following molecules, which have polar covalent bonds:a. A central atom with three identical bonded atoms and one lone pair.