(a)- Time
(b)- Heat produced(i guess)
(c)- Material
this is what I think, hope it helps
Answer:
5 atoms
Explanation:
According to the law of conservation of mass, "matter is neither created nor destroyed in the cause of a chemical reaction".
We finish with what we start with in a chemical reaction. Although new species might form, the number of atoms on both sides of the expression will still be maintained.
All chemical reactions obey this law of conservation.
Answer:
[Ne] 3s2 3p2
Explanation:
Neon (Ne) is the noble gas right before silicon (Si).
Then right after neon is the 3s subshell. It has two electrons and is full.
After 3s comes the 3p subshell, and silicon only has two electrons in the 3p subshell (you can just count the electrons in each subshell on your periodic table).
<u>U</u> <u>VORBELLO</u> <u>FRANÇAIS</u><u>?</u><u>?</u><u>?</u>
Answer: The reactivity of group 7 decreases as we move down the group because:
Explanation:
The elements of group 7 that is fluorine to iodine. The halogens are non metals and they react with metals to gain electrons. The metals loose electrons and the non metal gains it.
As we move down the group the atomic radius gets bigger( more electron and more proton) and as a result the outer shells move further away from the nucleus.
There is more distance between the negatively charged electrons and positively charged nucleus.
Therefore the force of attraction between the shells and nucleus is lesser or weaker.
This makes attracting an extra electron from metals very difficult which results in weaker reaction.
Consequently, the reactivity decreases as we move down the group 7
