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>
The chemical reaction is written as:
2Zn + O2 = 2ZnO
We are given the amount of the product to be produced from the reaction. We use this value and the relation of the substances in the reaction to calculate what is asked. We do as follows:
2.10 g ZnO ( 1 mol / 81.408 g ) ( 1 mol O2 / 2 mol ZnO ) ( 32 g / 1 mol ) = 0.414 g O2 is needed
Answer:
they are the same element because they have the same number of protons and electrons,but a different number of neutrons
