Answer:
B. calcium has electrons in more energy levels than magnesium
Explanation:
atoms are made of three types of subatomic particles - electrons, protons and neutrons.
Neutrons and protons reside in the nucleus of the atom and electrons reside in energy shells
electronic configuration for both Ca and Mg are as follows
Mg - 2,8,2
Ca - 2,8,8,2
outermost energy shell of Mg with electrons is the third energy level
whereas outermost energy shell of Ca with electrons is the fourth energy shell
therefore Ca has a larger atomic radius than Mg as it has one more energy shell than Mg in which electrons reside
So to put them all in the same units we have
<span>2500 mL </span>
<span>250 mL </span>
<span>25mL </span>
<span>2,500,000,000mL </span>
<span>So the third one is the smallest</span>
It was the element of aluminium where they predict their properties <span />
The reaction is actually endothermic because delta H is positive, indicating that it absorbing heat.