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Chemistry

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Calculate the empirical formula of a compound containing 77.7% Iron and 22.3% of oxygen.

An empirical formula is the simplest whole number ratio of atoms of each element present in the compound.1) Divide by atomic relative mass to find the number of moles. 2) Find a ratio between the moles. 3...

Answered by Jeel S. • Chemistry tutor

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A solution of acetic acid and sodium acetate was prepared, by dissolving 4.1 g of sodium acetate in 750 cm^3 of 0.085 mol/dm^3 acetic acid, at 25 degrees. 10 Cm^3 of 2 mol/dm^3 HCl was added. Ka is 1.76*10^-5, calculate and explain the change in pH

The first thing to do in any calculations question is to list out what you have, and what the question is asking you. In this case, the question wants pH, which is -log[H+]. So what we need is [H+]. We ha...

Answered by Alex M. • Chemistry tutor

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Explain the resistance to bromination of benzene in comparison to phenol.

In phenol, one of the lone pairs of electrons in a p-orbital of the oxygen atom in the -OH group overlaps with the delocalised ring of electrons in the ring. This lone pair is partially d...

Answered by Cerys H. • Chemistry tutor

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