Select all that apply. select all the correct statements about ion sizes below. check all that apply. au3+ is smaller than au+ as3− is smaller than p3−. au+ is smaller than au3+. na+ is smaller than k+. p3− is smaller than as3−. k+ is smaller than na+.

The answer is:
1. Au3+ is smaller than Au+
2. P3− is smaller than As3−
3. Na+ is smaller than K+

1. Au3+ is smaller than Au+ because an atoms get smaller when electrons are removed. So, the more electrons, the greater is the ionic radius. Au3+ has two less electrons than Au+ so Au3+ must be smaller than Au+.
2. P3- is smaller than As3- because P3- has a smaller ionic radius. Although these two ions have the sam number of electrons, they are not the same size. As is located below P in the Periodic table of elements. Going down the group of elements, extra layers of electrons are added resulting in bigger ionic radius. So, As3- has bigger ionic radius than P3-.
3. Na+ is smaller than K+ for the same reason as the P3- is smaller than As3-. Na is located above K in the Periodic table of elements.

Centration is the correct answer

The answer is joseph is observing the colour of the reaction mixture to see whether proteins are present in the given solution.