Bestie this subject is scinece.....
Answer:
helium
Explanation:
By losing an electron, they look like the noble gas that immediately precedes them on the periodic table.
A. proton donating is often referring to Hydrogen donating in acids. See the extra H+ in common acids: HCl, H2SO4
Answer:
a: 1
b: 4.5x10⁻⁴
c: 1.125x10⁻⁶
[H₃O⁺] = 0.000859M
Explanation:
As HNO₂ is a weak acid, its equilibrium in water is:
HNO₂(aq) + H₂O(l) ⇄ H₃O⁺(aq) + NO₂⁻(aq)
Equilibrium constant, ka, is defined as:
ka = 4.5x10⁻⁴ = [H₃O⁺] [NO₂⁻] / [HNO₂] <em>(1)</em>
Equilibrium concentration of each specie are:
[HNO₂] = 0.00250M - x
[H₃O⁺] = x
[NO₂⁻] = x
Replacing in (1):
4.5x10⁻⁴ = x × x / 0.00250M - x
1.125x10⁻⁶ - 4.5x10⁻⁴x = x²
0 = x² + 4.5x10⁻⁴x - 1.125x10⁻⁶
As the quadratic equation is ax² + bx + c = 0
Coefficients are:
a: 1
b: 4.5x10⁻⁴
c: 1.125x10⁻⁶
Now, solving quadratic equation:
x = -0.0013 → False answer, there is no negative concentrations.
<em>x = 0.000859</em>
As [H₃O⁺] = x; <em>[H₃O⁺] = 0.000859M</em>
I hope it helps!
On plato its D. I looked at Yahoo and there was an explanation for D.
