First, we need to get moles of HA =molarity * volume
= 0.1 m * 0.075 L = 0.0075 moles
moles of NaOH = molarity * volume
= 0.1 * 0.03 L = 0.003 moles
from the reaction equation:
HA(aq) + NaOH(aq) → NaA(aq) + H2O(l)
that means the final moles' HA = 0.0075 - 0.003 =0.0045 moles
when the total volume is = 0.075 + 0.03 L = 0.105 L
∴ [HA] = moles / volume
= 0.0045 / 0.105 L = 0.043 m
[A^-] = 0.003 / 0.105 L = 0.029 m
then by using H-H equation:
PH = Pka + ㏒[A^-] / [HA]
by substitution, we can get Pka:
5.5 = Pka+ ㏒ (0.029 /0.043)
∴ Pka = 5.67
when Pka = - ㏒Ka
5.67 = -㏒ Ka
∴Ka = 2 x 10^-6
In this question, you are given the gasoline density (0.749g/ml) and volume of the gasoline (19.2 gallons). You are asked the mass of the gasoline in pounds. Then you need to change the grams into pounds and the ml into gallons. The calculation would be:
mass of gasoline= density * volume
mass of gasoline= 0.749g/ml * (1 pound/453.592grams) * 3785.41ml/gallon * 19.2 gallon= 120 pounds
B elements
thank you
your welcome
wozmain
Answer:
The answer to your question is: letter C
Explanation:
Al ⁺³ + S⁻² ⇒ Al₂S₃
Answer:
P.S
Explanation:
Because sulphur has low electronegative magnitude, hence low polarity potential.
The sulphur atom doesn't not get distorted hence increase in ionic degree character.