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Why does the atomic radius of an atom decrease as you go across a period?

The atomic radius is often defined as being one half the distance between the two nuclei in a homonucleur diatomic molecule. In general, there is a decrease in atomic radius as you go across a period. Thi...

Answered by Louise E. • Chemistry tutor

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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

8193 Views

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

71768 Views

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

3645 Views

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

2403 Views