A. what is the total number of valence electrons in the polyatomic ion of ammonium? 5, 6, 7, 8, 10

8

Explanation:

Ammonium ion is formed when ammonia reacts with hydrogen ion

In the nitrogen has 5 valence electron and there are 4 hydrogen each has 1 valence electron

So total number of valence electron =4+5=9

But has 1 positive charge on it, it means it losses 1 electron

So total number of valence electron in poly atomic ion of    is 9-1=8

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.