Question

1. complete the following

how many valence electrons does bromine have? (first blank)
how many bonding electrons does bromine have? (second blank)
how many valence electrons does phosphorus have? (third blank)
how many lone pairs does phosphorus have? (fourth blank)
(record your four - digit answer in the numerical - response section below.)
your answer:

Explanation:

Step1: Determine Br valence electrons

Bromine is in Group 17. Elements in Group 17 have 7 valence electrons. So bromine has 7 valence electrons.

Step2: Determine Br bonding electrons

In a Br - Br bond (in $Br_2$ for example), each Br atom contributes 1 electron to the bond, so the number of bonding electrons for a single - bonded Br is 2.

Step3: Determine P valence electrons

Phosphorus is in Group 15. Elements in Group 15 have 5 valence electrons. So phosphorus has 5 valence electrons.

Step4: Determine P lone - pairs

Phosphorus has 5 valence electrons. In a molecule like $PH_3$, it forms 3 bonds with hydrogen. So the number of non - bonding electrons (lone - pair electrons) is $\frac{5 - 3}{2}=1$ lone pair.

Answer:

7251