<span>The alkali metals and hydrogen are reactive because they have only one electron to give in order to complete their valence shell. It is easier to give that one electron so when given the opportunity they will. This means they will react with anything polar or willing to take an electron.</span>
Answer:
B. 126
Explanation:
the scale is 1 to 42 so the scale would be:
3 cm:x cm
3 * 42 = 126 cm
