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3 years ago

8

A student sets up the following equation to solve a problem in solution stoichiometry. (The ? stands for a number the student is

going to calculate.) Enter the units of the student's answer
(1.26mol)1mL10^−3L / (7.9mol/L)= ?

1 answer:

Leni [432]3 years ago

3 0

Answer:

mL * L²

Explanation:

The question in t his problem is to calculate the units of the final answer.

The units in the numerator is mol, ml and L.

The unit in the denominator is mol/L

This leads us to;

Numerator / Denominator = mol * mL * L / (mol / L )

The final units is mL * L²

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You determine that it takes 26.0 mL of base to neutralize a sample of your unknown acid solution. The pH of the solution was 7.8

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Complete Question

You determine that it takes 26.0 mL of base to neutralize a sample of your unknown acid solution. The pH of the solution was 7.82 when exactly 13 mL of base had been added, you notice that the concentration of the unknown acid was 0.1 M. What is the pKa of your unknown acid?

Answer:

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Explanation:

From the question we are told

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The chemical equation of the reaction is

$HA_{(aq)} + OH^-_{(aq)} --------> A^{+}_{(aq)} + H_2 O_{(l)}$

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Substituting value

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this mathematically represented as

$N_B ' = N_B - N_B = 0$

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$N_A ' = N_A - N_B$

$= 0.0009\ moles$

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$pH = pK_a + log \frac{[base]}{[acid]}$

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