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There are two isotopes of element A. Information about the two isotopes is shown in Table 4. Table 4 Mass number of the isotope 6 7 Percentage abundance 92.5 7.5 Use the information in Table 4 to calculate the relative atomic mass of element A. Give your

92.5/100 x 6 = 5.557.5/100 x 7= 0.5255.55 + 0.525 = 6.075= 6.08 (2dp)

Answered by Natasha C. • Chemistry tutor

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Describe why diamond is hard and graphite is soft?

Diamond and graphite both only have carbons and have covalent bonding involved.Diamond has a giant covalent lattaice and each carbon atom is bonded to 4 other carbon atoms.Graphite on the other hand...

Answered by Muhammad Saleem R. • Chemistry tutor

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What is a mole and the calculations used to find the number of moles?

A mole in chemistry is a unit of amount. Similar to saying a dozen is 12, a mole is 6.022x10^23 atoms, conveniently called Avogadro's number. If we take one mole of carbon atoms, this is equal to a mass o...

Answered by Tutor165769 D. • Chemistry tutor

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State an explain the result of an increase in temperature on the following equilibria: N2 (g) + 02 (g) <-> 2 NO (g) (delta H = +180kJmol-1)

An increase temperature favours the endothermic direction of an equilibrium reaction; this is because there is more energy in the surroundings to accommodate for the energy that will be taken into the sys...

Answered by Samuel G. • Chemistry tutor

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How do you work out the limiting reagent in a reaction?

The limiting reagent is the chemical substance that isn't in excess in the reaction compared to the other components. The way to calculate which reagent limits the reaction and how it progresses is to cal...

Answered by Fiona S. • Chemistry tutor

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