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The acid dissociation constant, Ka, of ethanoic acid is 1.78 x 10^-5 at 298K. Given that the concentration of a sample of ethanoic acid is 0.4moldm^-3, calculate its pH at 298K.

Using the acid dissociation equation, Ka = [H+][A-]/[HA]. (where Substitute the known values into the concentration to give 1.78x10^-5= [H+][A-]/0.4 . Because the acid is dissociating in solutio...

Answered by Sita R. • Chemistry tutor

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What was the main causes of the First World War?

The causes of the First World War are numerous and varied, with long and short term factors but the main reason was the formation of Germany threatening the Balance of Power of Europe. Britain's foreign p...

Answered by Gareth K. • History tutor

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The length of a rectangle is five times the width. The area of the rectangle is 1620cm2. Work out the width of the rectangle.

For this question, we need to know the formula for finding the area of a rectangle is (length * width)From the question, Width = w; Length = 5wArea = 5w *w =1620cm². therefore, 5w² =...

Answered by Eme H. • Maths tutor

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Please give a short overview what the League of Nations was and why it was found.

The League of Nations was an international organization which resulted out of the Paris Peace Conference that eventually ended the First World War. Even though then U.S.-President Woodrow Wilson initiated...

Answered by Hannah M. • History tutor

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What is the difference between the pretérito indefinido and the pretérito imperfecto?

Using the examples of "Fui a la playa" for the pretérito indefinido and "Iba a la playa" for the pretérito imperfecto, we can translate both as "I went to the beach". However...

Answered by Charlette P. • Spanish tutor

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