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3 years ago

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08.04 MC) An unknown solution has a pH of 7.2. Which of these chemicals is likely to cause the greatest decrease in the pH of th

e solution when added to the solution? (5 points) a HF b KOH c NH3 d HNO3

1 answer:

OLEGan [10]3 years ago

6 0

Answer:

HNO3

Explanation:

i have the test

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Solution :

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$\text {n NaOH}=1.29 \times 10^{-5}+6.31 \times 10^{-7}$

$= 1.35 \times 10^{-5} \text{ moles}$

Volume NaOH $= 1.35 \times 10^{-5} \text{ moles} \times \frac{1000 \text{ mL}}{1 \text{ mol}} = 0.0135 \text{ mL}$

Tris mass $H^+ = 0.02 \text{ mol} \times 157.6 \text{ g/mol}=3.152 \text{ g}$

Now to prepare the said solution we must mix:

$3.152 \text{ g Tris H} + 0.0135 \text{ mL NaOH} \ 1 M$ gauge to 1000 mL with water.

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