# A-level chemistry

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If anyone is struggling with their chemistry revision, or needs some tips on how to revise, feel free to ask in this thread or pm me (AQA spec only though)

I am an AQA chemistry tutor, and I understand that exams are approaching so I’m offering help to anyone who needs it

I am an AQA chemistry tutor, and I understand that exams are approaching so I’m offering help to anyone who needs it

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#2

(Original post by

If anyone is struggling with their chemistry revision, or needs some tips on how to revise, feel free to ask in this thread or pm me (AQA spec only though)

I am an AQA chemistry tutor, and I understand that exams are approaching so I’m offering help to anyone who needs it

**MMA-Medic**)If anyone is struggling with their chemistry revision, or needs some tips on how to revise, feel free to ask in this thread or pm me (AQA spec only though)

I am an AQA chemistry tutor, and I understand that exams are approaching so I’m offering help to anyone who needs it

i always get confused becuase in the formarion so stuff is halved or doubled

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(Original post by

can you explain bon harbor process to mea

i always get confused becuase in the formarion so stuff is halved or doubled

**dedfghjkl**)can you explain bon harbor process to mea

i always get confused becuase in the formarion so stuff is halved or doubled

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#4

the whole thing would be great please

(Original post by

what part of the born-Haber cycles do you want me to explain? All of it or just a few parts?

**MMA-Medic**)what part of the born-Haber cycles do you want me to explain? All of it or just a few parts?

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(Original post by

the whole thing would be great please

**dedfghjkl**)the whole thing would be great please

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(Original post by

how about aqua metal ions the inorganic chapter pls

**hm061**)how about aqua metal ions the inorganic chapter pls

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#8

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Send me you’re email address, I will send u a document that should help you out slightly

**MMA-Medic**)Send me you’re email address, I will send u a document that should help you out slightly

do you know how to calculate relative molecular mass of this question

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#9

(Original post by

friend i need your help

do you know how to calculate relative molecular mass of this question

**dyfugikholjp**)friend i need your help

do you know how to calculate relative molecular mass of this question

speed is v

so you now have k.e(given to you) and v(calculated) so use k.e =1/2mv² to calculate mass.

this mass is mass of one ion in kg so you times by 1000 to convert to grams and then you times by avogadros constant to work out mr.

you use avogadros constant because the mass you worked out from the k.e equation is the mass of one ion however mr is the mass of one mole of that atom or ion.

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#10

(Original post by

you've been given time and distance so you can use speed=distance/time to calculate speed of the ion.

speed is v

so you now have k.e(given to you) and v(calculated) so use k.e =1/2mv² to calculate mass.

this mass is mass of one ion in kg so you times by 1000 to convert to grams and then you times by avogadros constant to work out mr.

you use avogadros constant because the mass you worked out from the k.e equation is the mass of one ion however mr is the mass of one mole of that atom or ion.

**UnknownError404**)you've been given time and distance so you can use speed=distance/time to calculate speed of the ion.

speed is v

so you now have k.e(given to you) and v(calculated) so use k.e =1/2mv² to calculate mass.

this mass is mass of one ion in kg so you times by 1000 to convert to grams and then you times by avogadros constant to work out mr.

you use avogadros constant because the mass you worked out from the k.e equation is the mass of one ion however mr is the mass of one mole of that atom or ion.

speed=distance/time to calculate speed of the ion.

so is the distance is 1.50m

and the time is 1.23 x 10-5

so is the speed 1.50/1.23 x 10-5 =121951.2195V

so use k.e =1/2mv² to calculate mass.

help i am confused

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yeah this is right. Then once you have worked out mass, you need to multiply it by 1000 because you have been given the mass in Kg in the question and you want g. the mass you have worked out in the KE formula is the mass of one ion, and Mr/avogadros constant = mass of one atom/ion. sou you rearrange this to work out the Mr by multiplying the mass of the single ion with avogadros constant

hope this helps

hope this helps

(Original post by

**dyfugikholjp**)
(Original post by

you said reranging =

speed=distance/time to calculate speed of the ion.

so is the distance is 1.50m

and the time is 1.23 x 10-5

so is the speed 1.50/1.23 x 10-5 =121951.2195V

so use k.e =1/2mv² to calculate mass.

help i am confused

**dyfugikholjp;undefined**)you said reranging =

speed=distance/time to calculate speed of the ion.

so is the distance is 1.50m

and the time is 1.23 x 10-5

so is the speed 1.50/1.23 x 10-5 =121951.2195V

so use k.e =1/2mv² to calculate mass.

help i am confused

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#13

ho

how do i calculate mass

(Original post by

yeah this is right. Then once you have worked out mass, you need to multiply it by 1000 because you have been given the mass in Kg in the question and you want g. the mass you have worked out in the KE formula is the mass of one ion, and Mr/avogadros constant = mass of one atom/ion. sou you rearrange this to work out the Mr by multiplying the mass of the single ion with avogadros constant

hope this helps

**MMA-Medic**)yeah this is right. Then once you have worked out mass, you need to multiply it by 1000 because you have been given the mass in Kg in the question and you want g. the mass you have worked out in the KE formula is the mass of one ion, and Mr/avogadros constant = mass of one atom/ion. sou you rearrange this to work out the Mr by multiplying the mass of the single ion with avogadros constant

hope this helps

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rearrange the KE formula so m = KE/0.5v^2

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#15

ok i got that thanks

(Original post by

rearrange the KE formula so m = KE/0.5v^2

**MMA-Medic**)rearrange the KE formula so m = KE/0.5v^2

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#16

for this question is this the answer the enthalpy of lattice formation for ceasium iodide in table 1 is a value obtained by experiment.the values obtained by calculation using perfect ionic model is -582deduce what these valuse indicate about caesium iodide

close to perfectly ionic as possible - as showcased by the very small difference between the two values. close to perfectly ionic as possible - as showcased by the very small difference between the two values.

close to perfectly ionic as possible - as showcased by the very small difference between the two values. close to perfectly ionic as possible - as showcased by the very small difference between the two values.

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yeah so if the experimental value is equal to or close to the theoretical value, then the molecule is perfectly ionic and consists of perfect spheres. If the values are different, then it contains covalent character

(Original post by

for this question is this the answer the enthalpy of lattice formation for ceasium iodide in table 1 is a value obtained by experiment.the values obtained by calculation using perfect ionic model is -582deduce what these valuse indicate about caesium iodide

close to perfectly ionic as possible - as showcased by the very small difference between the two values. close to perfectly ionic as possible - as showcased by the very small difference between the two values.

**dyfugikholjp**)for this question is this the answer the enthalpy of lattice formation for ceasium iodide in table 1 is a value obtained by experiment.the values obtained by calculation using perfect ionic model is -582deduce what these valuse indicate about caesium iodide

close to perfectly ionic as possible - as showcased by the very small difference between the two values. close to perfectly ionic as possible - as showcased by the very small difference between the two values.

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#18

(Original post by

yeah so if the experimental value is equal to or close to the theoretical value, then the molecule is perfectly ionic and consists of perfect spheres. If the values are different, then it contains covalent character

**MMA-Medic**)yeah so if the experimental value is equal to or close to the theoretical value, then the molecule is perfectly ionic and consists of perfect spheres. If the values are different, then it contains covalent character

close to perfectly ionic as possible

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with what you're telling me, i think you will, because you are implying that it has no covalent character

(Original post by

so i wont get the mark for saying

close to perfectly ionic as possible

**dyfugikholjp**)so i wont get the mark for saying

close to perfectly ionic as possible

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#20

and for the question that asks the meaning of the term periodicity can i say trends in element properties with increasing atomic number

and get full marks

and get full marks

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