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A 25 cm3 sample of an unknown concentration of sulfuric acid was titrated against 0.1 mol dm-3 sodium hydroxide. The average titre was 20 cm3. Calculate the concentration of the sulfuric acid.

Balanced equation: H₂SO₄ + 2NaOH → 2H₂O + Na₂SO₄moles of NaOH = c x v = 0.1 mol dm^-3 x (20/1000) dm³ = 0.002 molStoichiometry: ...

Answered by Joseph K. • Chemistry tutor

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State and explain whether NaCl and Mg can conduct electricity in both the solid and molten states.

NaCl cannot conduct electricity in the solid state as the ions are held in an ionic lattice and therefore are not free to conduct. NaCl can conduct in the melt as the ions become mobile and therefore are ...

Answered by Joseph K. • Chemistry tutor

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Why do first ionisation energies decrease down a group but increase across a period?

The nucleus contains positively charged protons which attract the negative electrons, the first ionisation energy is the energy required to overcome this attraction and remove 1 electron As you go down a ...

Answered by Amy M. • Chemistry tutor

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Explain how the properties and structure of solid salt change when it dissolves in water

When a salt is solid it forms a a crystaline structure and a fixed ionic lattice. This means the ions are stationary and cannot move in the solution and therefore is unable to conduct electricity. However...

Answered by Lara E. • Chemistry tutor

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What does Le Chatelier's principle say happens to an equilibrium when temperature is changed or a catalyst is added?

The temperature moves the equilibrium differently depending on if the forwards reaction is exothermic or endothermic. If its endothermic the equilibrium moves to the right giving more products. The additi...

Answered by • Chemistry tutor

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