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Ionisation energy question help!

1470253519984-1676330518.jpg hi, can anyone help me with 2 c please? I don't get how c can be worked out as all the sequences given show a decrease as a trend. Why is there an increase in the second ionisation from Si-Ar in the second period because Si should have the highest 2nd I.E since it only has 1 electron in its outer shell. Is this because the of increase in nuclear charge?
Thanks
(edited 7 years ago)
hi ok so first think of the factors that affect ionisation energy :
nuclear charge
distance from the nucleus(atomic radius)
shielding
think which of these factors are increased or decreased when the elements lose eletrons

for example oxygen compared to nitrogen and second ionisation energy:

oxygen still has the higher nuclear than nitrogen as it has more protons

oxygen would have the smaller atomic radius as the protons pulls the shells in (and they have the same amount of shells)

shielding again same shells so sheilding has no real effect

so I would oxygen would have the higher second ionisation energy as its distance from the nucleus is smaller and it has a higher nuclear charge

do this with all the trends and see

sorry if its not clear I dont want to give away the answer but dont want to be unclear in explaination



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Reply 2
Original post by GabbytheGreek_48
hi ok so first think of the factors that affect ionisation energy :
nuclear charge
distance from the nucleus(atomic radius)
shielding
think which of these factors are increased or decreased when the elements lose eletrons

for example oxygen compared to nitrogen and second ionisation energy:

oxygen still has the higher nuclear than nitrogen as it has more protons

oxygen would have the smaller atomic radius as the protons pulls the shells in (and they have the same amount of shells)

shielding again same shells so sheilding has no real effect

so I would oxygen would have the higher second ionisation energy as its distance from the nucleus is smaller and it has a higher nuclear charge

do this with all the trends and see

sorry if its not clear I dont want to give away the answer but dont want to be unclear in explaination



Posted from TSR Mobile


Hi, thanks for helping. I understand that these are the factors affecting the I.E, which is why I don't understand Why Si, P and S don't show an increase in 2nd I.E because Si only has 1 electron left to be removed, so surely it will need the most energy out of all? But I found that the 2nd I.E increases from Si to Ar in the period 2, is this because of the increase in the nuclear charge from Si to Ar. So although si only has one electron left in its outer shell, since Cl has the highest nuclear charge, Cl will have the highest 2nd I.E in the period 2 because it has the strongest nuclear attraction? Thanks
yeah its because of the nuclear charge however cl might not have the highest as if you think about it after losing one electron its second ionisation will be like sulphurs first . and idk if you know but sulphur has a low first ionisation energy for a particular reason
hint:look at the sub shells abd the amount of electrons in each


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sorry ignore my former comment about cl but yeah the nuclear charge outweighs it

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Original post by GabbytheGreek_48
sorry ignore my former comment about cl but yeah the nuclear charge outweighs it

Posted
What is the definition of ionisation energy ?
Reply 6
Original post by Calorins Atieno


Posted
What is the definition of ionisation energy ?


The ionization energy (IE) is qualitatively defined as the amount of energy required to remove the most loosely bound electron, the valence electron, of an isolated gaseous atom to form a cation.
Reply 7
Original post by alow
The ionization energy (IE) is qualitatively defined as the amount of energy required to remove the most loosely bound electron, the valence electron, of an isolated gaseous atom to form a cation.


So in this case, is it right to say that the reason 2nd I.E increases from Si to Ar is because the nuclear charge plays a bigger role? So although Si only has one more electron to be removed, since Ar has the most protons, more energy is needed to remove one electron than Ar compared to Si? Thanks
Reply 8
Original post by GabbytheGreek_48
yeah its because of the nuclear charge however cl might not have the highest as if you think about it after losing one electron its second ionisation will be like sulphurs first . and idk if you know but sulphur has a low first ionisation energy for a particular reason
hint:look at the sub shells abd the amount of electrons in each


Posted from TSR Mobile


So although Si only has one more electron to be removed, since Ar has the most protons, more energy is needed to remove one electron than Ar compared to Si? Is this right? Cheers

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