P = pressure, V = volume, T = absolute temperature k = constant.
8 valence electrons means that the element is stable. When we hear stable, we know the group to look at! Noble gases all have 8 valence electrons making them stable and have a full octet.
Here are some:-
Krypton
Argon
Neon
Answer:
4.35 * 10^-8 M
Explanation:
Since the concentration of the hydronium ion= 2.3 X 10^-7 M
And we know that;
[H3O^+] [OH^-] = 1 * 10^-14
[H3O^+] = concentration of the hydronium ion
[OH^-] = concentration of the hydroxide ion
So;
[OH^-] =1 * 10^-14/[ H3O^+]
But [H3O^+] = 2.3 X 10^-7 M
[OH^-] = 1 * 10^-14/2.3 X 10^-7
[OH^-] = 4.35 * 10^-8 M
Answer:
39.7 %
Explanation:
magnesium + oxygen ⟶ magnesium oxide
10.57 g 6.96 g 17.53 g
According to the <em>Law of Conservation of Mass</em>, the mass of the product must equal the total mass of the reactants.
Mass of MgO = 10.57 + 6.96
Mass of MgO = 17.53 g
The formula for mass percent is
% by mass = Mass of component/Total mass × 100 %
In this case,
% O = mass of O/mass of MgO × 100 %
Mass of O = 6.96 g
Mass of MgO = 17.53 g
% O = 6.96/17.53 × 100
% O = 0.3970 × 100
% O = 39.7 %
