Answer:
[HAc] = 0.05M
[Ac⁻] = 0.20M
Explanation:
The Henderson-Hasselbalch formula for the acetic acid buffer is:
pH = pka + log₁₀ [Ac⁻] / [HAc]
Replacing:
5.36 = 4.76 + log₁₀ [Ac⁻] / [HAc]
3.981 = [Ac⁻] / [HAc] <em>(1)</em>
Also, as total concentration of buffer is 0.25M it is possible to write:
0.25M = [Ac⁻] + [HAc] <em>(2)</em>
Replacing (2) in (1)
3.981 = 0.25M - [HAc] / [HAc]
3.981 [HAc] = 0.25M - [HAc]
4.981 [HAc] = 0.25M
<em>[HAc] = 0.05M</em>
Replacing this value in (2):
0.25M = [Ac⁻] + 0.05M
<em>[Ac⁻] = 0.20M</em>
I hope it helps!
Answer:
Both are B. Hope this helps.
The mass change, or the mass defect, can be calculated by the formula that is very known to be associated with Albert Einstein.
E = Δmc²
where
E is the energy gained or released during the reaction
c is the speed of light equal to 3×10⁸ m/s
Δm is the mass change
(1.715×10³ kJ)(1,000 J/1 kJ) = Δm(3×10⁸ m/s)²
Δm = 1.91×10⁻¹¹ kg
Answer:
Na2B4O7 + H2SO4 + 5H2O → 4H3BO3 + Na2SO4
Explanation:
The unbalanced equation is given as;
Na2B4O7 + H2SO4(aq) + H2O → H3BO3(s) + Na2SO4(aq)
Balancing the equation of the reaction involves making sure the number of moles of elements in the reactants to be equal to the number of moles of the element of the products.
The balanced equation is given as;
Na2B4O7 + H2SO4 + 5H2O → 4H3BO3 + Na2SO4
Answer:
Noble gases are non-metals
