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An iron-alloy nail (2.41g) is dissolved in 100cm3 acid. 10cm3 portions of this solution are titrated with KMnO4 (0.02M) and 9.80cm3 of KMnO4 was needed to react with iron solution. What % of iron by mass is in the nail?

This is a common example of a titration calculation which can be broken down into several key steps:1) Write a balanced equation for the redox reaction:MnO4 - + 8H+ + 5Fe2+ --> Mn2+ + 4H2O + 5Fe3+(This...

Answered by Amy C. • Chemistry tutor

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What are the three pieces of evidence that disprove the Kekulé model of Benzene?

The enthalpy change of hydrogenation is less exothermic than suggested by the Kekulé model ( -208kJmol^-1 instead of the expected -357kJmol^-1), meaning Benzene is more thermodynamical...

Answered by • Chemistry tutor

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What are the three different physical states and how do they differ?

There are three different physical state configurations of a substance, solid, liquid and gas. The different states are caused by the arrangement and movement of the particles that make up that substance....

Answered by Samuel W. • Chemistry tutor

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Metals can be extracted fromt their oxides via the process of electrolysis. Positive metal ions are attracted to the negative electrode. explains what happens at the negative electrode. (2 marks)

Metal ions gain electrons to form metal atoms.(Eg Al3+ + 3e- ----> Al)

Answered by Tamsin D. • Chemistry tutor

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Describe the bonding in i)NaCl, ii) HCl, iii) Mg

Sodium chloride forms an ionic bond, between metallic sodium and non-metallic chlorine. An atom of sodium transfers an electron to an atom of chlorine, forming a positive...

Answered by Yasmin B. • Chemistry tutor

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