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Discuss the trend in first ionisation energies across the second period of the periodic table.

First of all we must appreciate the general trend in these ionisation energies. The will always be endothermic (takes in energy) since we must put energy into a system to overcome the strong electrostatic at...
JE
Answered by Jake E. • Chemistry tutor
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Explain why the second ionisation energy of boron is higher than the first ionisation energy of boron.

Boron is the 5th element in the periodic table, and has an electron configuration 1s 2 2s 2 2p 1 . The first ionization energy of Boron is the energy required to remove the single 2p electron, while the seco...
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Answered by Adelina I. • Chemistry tutor
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Can you explain what stoichometry actually is and why the ratio is not the same as the number of moles?

Stoichiometry is just a way of relating two species that react, in a ratio. EXAMPLE: 1A + 2B -> 3C Now usually this would be written as A + 2B -> 3C but I've written the 1 to exaggerate the point. Now ...
MR
Answered by Michael R. • Chemistry tutor
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0.250 g of a hydrocarbon known to contain carbon, hydrogen and oxygen was subject to complete combustion and produced 0.3664 g of CO2 and 0.1500 g of H2O. What is the empirical formula of this hydrocarbon?

The first step here is to determine the mass of C in CO 2 and the mass of H in H 2 O. This is done by dividing the relative atomic mass, Mr, by the relative molecular mass of the compound, M CO2 or M H2O , a...
JH
Answered by Joshua H. • Chemistry tutor
13713 Views

1.5 g of hydrocarbon undergoes complete combustion to give 4.4 g of CO2 and 2.7 g of H2O. Given this data, what is the empirical formula of this hydrocarbon?

The first step here is to determine the mass of C in CO 2 and the mass of H in H 2 O. This is done by dividing the atomic mass by the molecular mass and then multiplying by the mass of compound produced. For...
JH
Answered by Joshua H. • Chemistry tutor
87944 Views