Hey there!
Solid Sodium and water will react spontaneously and release energy. This is based on the reactivity series. Sodium is a highly reactive metal and hence, it is placed at the top of the reactivity series. This is because it loses its outermost electron very readily. When it comes in contact with water, it reacts with it violently to form sodium hydroxide and hydrogen gas. This reaction is exothermic and hence, accompanied with a release of energy. Gold lies at the bottom of the reactivity series as it is very stable and does not give away its outermost electrons easily. Therefore, when it comes in contact with water, there is no reaction and no release of energy.
I don't know what you mean by the question, but in science it is Newton's second law.
"The second law explains how the velocity of an object changes when it is subjected to an external force."
I hope this helped!+*♡
2. <span>1/8 = (1/2)³ </span>
<span>so it's 3 half lives.</span>
