Select the keyword or phrase that will best complete each sentence about the three general rules of for drawing Lewis structures.a. main group b. hafnium c. valence d. hydrogen e. core f. transition metal1. Draw only__the electrons. 2. Give every___element (except hydrogen) an octet of electrons. 3. Give eachtwo electrons.

1. Draw only the valence electrons.

2. Give every element main group element (except hydrogen) an octet of electrons.

3. Give each hydrogen two electrons.

Explanation:

Lewis structures are used to describe the arrangement or configurations of the valence electrons of molecules and polyatomic ions involved in electronic bonding. A Lewis structure consists of the symbols of the elements in the molecule surrounded by dots with each dot representing each of the elements valence electrons. Also, the electrons shared between two elements are shown by dots between the two elements and these electrons are known as shared electron pairs. The valence electrons on atom that is not involved in bonding is known as lone pairs.

The three general rules for drawing Lewis structures are:

1. Draw only the valence electrons. Only the valence electrons of the atoms of elements are shown since they are the only electrons involved in chemical bonding.

2. Give every element main group element (except hydrogen) an octet of electrons. The complete eight valence electrons of the noble gases is associated with their stability. Thus, the main group elements show a tendency to form enough bonds to obtain eight valence electronsmin order to achieve stability. This is known as the octet rule. However, since the maximum number of valence electrons for elements in the first period of the period table is two, the noble gas helium has completely-filled valence shell containing two electrons known as a duplet. Hydrogen belongs to the first period and is therefore an exception tomthe octet rule.

3. Give each hydrogen two electrons. Hydrogen attains a duplet structure in accordance with the structure of helium