<span>These values also increase from the
bottom to the top of a group because the size of the atom decreases, resulting
in a smaller distance between the nucleus and the valence electron shell, which
increases the attraction between the protons and electrons.</span>
Since Group 2 alkali earth metals have 2 valence electrons, they tend to lose those 2 when forming ionic bonds. And the Loss of Electrons = Oxidation (L.E.O. for short). Therefore this group, including Mg and Ca, have an oxidation of [+2].
So the correct answer is C) +2
Answer:
I'm really sorry but I didn't understand your question
Answer:
A
Explanation:
B and D have to do with plants
and C has nothing to do with cellular resporation.
1) Molecular formula of ammonium sulfide
(NH4)2 S
2) That means that there are 2*4 = 8 atoms of hydrogen in each molecule of ammoium sulfide, so in 5.20 mol of molecules will be 8 * 5.20 mol = 41.6 moles of atoms of hydrogen
3) To pass to number of atoms multiply by Avogadro's number: 6.022 * 10^23
41.6 moles * 6.022 * 10^23 atoms / mol = 250.5 * 10^23 = 2.50 * 10^25 atoms
Answer: 2.50 * 10^25