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In aqueous solution, sulphuric acid dissociates into ions in 2 stages. The pKa for the first dissociation is -3. Calculate the pH of a 0.025 mol dm-3 solution of sulphuric acid using the pKa value of the 1st dissociation.

Ka = 10^-pKa = 10^--3 = 1000[H⁺] = √ Ka [0.025] = √1000 x 0.025 = 0.791pH = -log [H] = -log(0.791) = 0.102 = 0.1

Answered by Octavia M. • Chemistry tutor

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How do I conjugate a present tense verb ending in er?

Firstly when a verb is not conjugated (ie. to go rather than I go) , this is known as the infinitive. In french an example could be

Answered by Matthew H. • French tutor

1157 Views

How do you form the perfect tense in German?

The perfect tense is a compound tense. This is because a sentence in the perfect tense is constructed from an auxiliary verb and a past participle.Let's use the simple sentence "I have played" a...

Answered by Tom G. • German tutor

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Express 280 as a product of its prime factors.

2 * 2 * 2 * 5 * 7 = 280

Answered by Danny S. • Maths tutor

4585 Views

What makes a perfect virus?

This is an example of a scientific question at an Oxbridge medical interview. The purpose of this type of question is to assess whether you have the ability to work something unfamiliar from first princip...

Answered by Triya C. • Oxbridge Preparation tutor

1751 Views