Question

when three or more atoms and join together:​

Answer 1

Answer:

Sometimes a compound or as with many atoms, a molecule made up of itself. For example, Na(sodium) and Cl(chlorine) are atoms when combined give us NaCl which we know as common table salt. As individual atoms, sodium will spontaneously combust with water or react with atmospheric oxygen which can be problematic. It is usually stored in oil. Chlorine, existing as a molecule is toxic and can destroy your lungs if inhaled. It was actually used extensively during world war 1 against soldiers with devastating results. The amazing thing is when it is combined with sodium, gives us salt which is essential for our bodies to remain in a healthy state. This brings us to are second state that can exist when atoms combine. Returning to the previous element Chlorine, it usually can't exist as a single atom but rather it bonds covalently with itself giving giving us chlorine gas. Other examples of atoms that form molecules with itself are oxygen, nitrogen, hydrogen (there are other examples). I hope I haven't been too long-winded with my answer and thank you for the question.

P.S

When Na and Cl combine they produce NaCl but as I've written it, can be a little deceptive. In a chemical reaction, matter is conserved. The number of Na and Cl atoms must balance against the product that exists after the reaction. Returning to the first chemical reaction we have

Na+Cl -> NaCl

But recall Cl can only exist as a molecule of itself at STP (standard temperature and pressure) so to balance the equation we write:

Na+Cl(2) pretend the 2 is a subscript, I'm not sure how to show that in quora (if anyone knows I would be grateful if you explain how to show that):

Na+Cl(2) -> 2NaCl, but it is still not correct so we write:

2Na+Cl(2) -> 2NaCl

Which reads

2 molecules of sodium combined with 1 molecule of chlorine gas gives two molecules of table salt.

That is all.

HOPE THIS HELPS YOU

Answer 2

Explanation:

An molecule is formed when two or more atoms join together chemically. If atoms combine that are of two or more different elements , we call that a compound. All compounds are molecules , but not all molecules are compounds.

Hope this answer may help u mate