Answer is: <span>a hill over which a wagon is pushed.
</span>For all chemical
reaction some energy is required and that energy is called activation
energy (<span>energy
that needs to be absorbed for a chemical reaction to start)<span>.
There are two types of reaction: endothermic
reaction (chemical reaction that absorbs more energy than it releases)
and exothermic reaction (chemical reaction that releases more energy than
it absorbs).
</span></span>R<span>eactions
occur faster with a catalyst because they require less activation energy.</span>
Answer:
2
Explanation:
Each orbital can hold two electrons. One spin-up and one spin-down.
Answer:
B. People live longer than they used to
Explanation:
None of the other answers are correct.
Answer:
Electrons orbit the nucleus.
