Because size of an atom INCREASES from top to bottom and DECREASES from left to right on the periodic table. If to elements are in the same period they can't increase in size based on the up or down trend. Instead, notice that Alkali Metals are LEFT of Alkaline Earth Metals. Therefore, the Alkali Metal will be larger than the Alkaline Earth Metals.
Your answer is <span>D) The angle of light from the sun as it reflects off the moon and viewed from the Earth's surface because of the way the sun hits the moon one side has to light the other doesn't and when the moon rotates the sun hits another part of the moon.
If you need more help I would be glad to help!
</span>*~"AB84"~*
(0.878)(267.8) + (0.122)(269.9)=
268 u (three sig fig)
Check my calculations
Two 1+ ions are needed in order to balance one 2- ion.
