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Explain why a buffer solution is formed when excess weak acid is added to a strong base

Because the weak acid is in excess, all of the strong base will react to form water and a salt of the acid. Since there is still some of the acid in the reaction mixture at the end point, an acidic buffer...

Answered by Ryan K. • Chemistry tutor

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Describe briefly how you would show that manganese(II) ions catalyse the reaction between manganate(VII) ions and ethanedioate ions, in dilute sulphuric acid.

Mix the reagents and record the time taken for a specific observation, e.g. disappearance of colour which is characteristic for this chemical reaction. We repeat this step and add more manganese(II) ions;...

Answered by Sukhjeewan S. • Chemistry tutor

6319 Views

Relationship between moles and Avogadro's constant

Moles equation is moles= mass/RFM Avogadro's constant is 6.x 10²³.

1 mole means 6x 10²³ atoms/molecules.

e.g. 2 mole of Cu weighs 128g. What is the weight of 1 Cu ato...

Answered by Joshny J. • Chemistry tutor

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What is the % yield if 12g of magnesium is dissolved in hydrochloric acid to produce 20g of magnesium chloride?

First we need to write the balanced equation for the reaction. In this case it is Mg + 2HCl -> MgCl₂ + H₂. Now we need to work out the maximum theoretical yield of MgCl₂

Answered by Holly W. • Chemistry tutor

6719 Views

With reference to valencies, describe and explain the differences in reaction as you go down group 1 of the periodic table for the reaction: metal + water -> Metal hydroxide + hydrogen.

As you descend the group, the reactions become more vigorous, more exothermic and have a higher rate of reaction. Lithium will just gently fizz and produce a gas, sodium will melt into a ball shape and fi...

Answered by George N. • Chemistry tutor

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