H2O
This equation is a double displacement reaction, and it forms H2CO3, which is very unstable and separates into H2O and CO2.
Multiply the number of each element by its mass on the periodic table.
Add them together.
Put the mass of carbon only over the total mass and multiply the result by 100 to get the percentage.
Answer:
2N₂ + O₂ → 2N₂O
Explanation:
Given equation:
N₂ + O₂ → N₂O
In balancing a chemical equation, the number of atoms on both sides of the expression must be the same.
To solve this problem, we use a simple mathematical approach;
put coefficients a,b and c
aN₂ + bO₂ → cN₂O
Conserving N;
2a = 2c
Conserving O:
2b = c
Let a = 1, c = 1 , b = 
multiply through by 4
a = 2, b = 1 and c = 2
Balanced equation is;
2N₂ + O₂ → 2N₂O
Answer:
B, C
Explanation:
The atoms or ions with the valid Lewis dot structures are B and C.
In A;
The Lewis structure of the carbon is correct. Each of the four dots represent the four valence electrons.
The nitrogen with one dot on top, left and to the bottom and has a charge of minus 3 is wrong. For it to have a charge of -3 it must have 8 lewis dots ( two on the top, right, bottom and to the left)
The nitrogen with four dots (on top, right, bottom and to the left) is wrong.
In B;
An oxygen has two dots on top and bottom and one dot to the left and to the right. This is correct , the 6 dots represent the valence electrons of oxygen.
In C;
A carbon has two dots on top, right, bottom and to the left and a charge of plus four. This is correct because the charge indicates that it has gained four extra electrons so its valence electrons is now 8.
In D;
An oxygen has two dots on top, left and to the bottom and a charge of minus 2. This is wrong because the lewis dots are incomplete. Two dots are missing.
