CO2 ; H20- They are the only ones that, on both sides, combined with another element and bonding of atoms
Answer:
A Chemical Reaction
Explanation:
There are 2 kinds of reactions physical and chemical. The digestion process often involves the use of digestive enzymes in your mouth and acid in your stomach.
While the number nuclear protons as given is 34, and therefore we deal with the element selenium, there are 2 more electrons than protons, and therefore this species has an overall
2
−
charge.
We represent this selenide ion as
S
e
2
−
. Do I win 5 pounds?
Z= 34, therefore the atom is selenium
Sun isn't actually planet but star. Really big ball made of gases. Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%). Sun is the biggest object in our Solar System. It's 99.86% of the total mass of the Solar System.
... wikipedia is really grat if you have questions like that ;)