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The question is incomplete. Complete question is attached below:
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Answer:
Given: conc. of HBr = 1.4 M
Volume of HBr = 15.4 mL
Volume of KOH = 22.10 mL
We know that, M1V1 = M2V2
(HBr) (KOH)
Therefore, M2 = M1V1/V2
= 1.4 X 15.4/22.10
= 0.9756 M
Concentration of KOH is 0.9756 M.
The correct answer B. increase the flame setting to produce more heat
The balanced chemical reaction would be expressed as follows:
2Na + Cl2 = 2NaCl
We are given the amount of sodium metal to be used reaction. This would be the starting value for the calculations. We do as follows:
6.25 g ( 1 mol / 22.99 g ) ( 1 mol Cl2 / 2 mol Na ) ( 22.4 L / 1 mol ) = 3.045 L Cl2 needed
Hope this answers the question.
pH of solution = 13.033
<h3>Further explanation</h3>
Given
2.31 g Ba(OH)₂
250 ml water
Required
pH of solution
Solution
Barium hydroxide is fully ionized, means that Ba(OH)₂ is a strong base
So we use a strong base formula to find the pH
[OH ⁻] = b. Mb where
b = number of OH⁻
/base valence
Mb = strong base concentration
Molarity of Ba(OH)₂(MW=171.34 g/mol) :

Ba(OH)₂ ⇒ Ba²⁺ + 2OH⁻(b=valence=2)
[OH⁻]= 2 . 0.054
[OH⁻] = 0.108
pOH= - log 0.108
pOH=0.967
pOH+pH=14
pH=14-0.967
pH=13.033