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Chemistry

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How can Diamond and Graphite both be made of carbon but be so different?

Graphite and Diamond are different because they have different structures. Both have Giant Covalent Structures, resulting in very high melting temperatures. However each carbon atom in Diamond has 4 coval...

Answered by Oghenebrume U. • Chemistry tutor

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What are the half equations representing the changes of Pb2+ and Br- in the electrolysis of lead bromide?

Pb2+ + 2e- -> Pb 2Br- -> Br2 + 2e- Lead ions undergo reduction (gain of electrons) at the negative electrode to form solid lead. Bromide ions undergo oxidation (loss of electrons) at the positive el...

Answered by Sophie F. • Chemistry tutor

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What observations would I expect to make if I dropped from magnesium into some hydrochloric acid? What is the balanced chemical equation?

Effervescence and the magnesium metal would dissolve. Mg + 2HCl --> MgCl2 + H2

Answered by Ollie W. • Chemistry tutor

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25cm3 of NaOH (2M) were titrated with 1.25M H2SO4. Write down the balanced reaction equation. Calculate the number of moles of NaOH used in the titration and hence deduce the volume of sulfuric acid used in the titration. Give your answer in dm3.

2NaOH + H2SO4 -> 2H2O + Na2SO4. moles = concentration x volume. #moles NaOH = 2M x (25/1000)dm3 = 0.05 mol. The reaction equations shows the ratio of alkali to acid is 2:1. The number of moles of H2SO4...

Answered by Tiffany W. • Chemistry tutor

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balance this equation C8H18 + O2 ---> CO2 + H2O

First split the equation in half. write down the number of each element there is on either side and then see how many more of that atom you need. make sure that there is the same number of carbons oxygens...

Answered by Meherun C. • Chemistry tutor

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