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Maths/chem question

Hi guys does anyone know the answer to this or how you would work it out? I have never seen a question like this before

The gold foil is:
4.00 × 10–7 metres thick
2400 atoms thick.
What is the diameter of one gold atom in metres?
Give your answer to 3 significant figures.
so 2400 atoms are 4x10^-7 m thick therefore 1 atom would be (4x10^-7) / 2400 I think.
Original post by lol9812
Hi guys does anyone know the answer to this or how you would work it out? I have never seen a question like this before

The gold foil is:
4.00 × 10–7 metres thick
2400 atoms thick.
What is the diameter of one gold atom in metres?
Give your answer to 3 significant figures.

Hi good to see you are laughing - my grandad [in India] goes to a laughing club where people get hysterical without any jokes lol - bit of physiology for you:angry: laughing releases endorphins and encephalins [the natural opioids - morphine-like substances] in your body, so you feel happy even in these tough times - now I am laughing cos I am happy for you!! :lol:

Coming to the point, yes @Glockity is q right [except I am not sure why he/she has an abbreviation for "litre" at the end].

So,
Diameter = 4 X 10^-7/2400 m
................= 4000 X 10^-10/2400 m
................= 1.67 X 10^-10 m

ALWAYS QUICKLY CHECK YOUR ANSWER, yeah? [we are reducing the value of 4 X 10^-7 by a factor of about 1/4 of 10000, agreed? - (1/4 of 10000 is 2500) [simple mental maths, which you will need if by chance you are doing the UCAT exam for medicine] - so dividing the thickness of foil by 10000 gives about 4 X 10^-11 then multiplying by 4 gives 16 X 10^-11, which is nearly exactly the same as the answer in bold - yippee!! Ok sorry, now your belly is in agony - lol even more: sorry!! :sorry:

Be safe!
M.
Original post by macpatgh-Sheldon
Hi good to see you are laughing - my grandad [in India] goes to a laughing club where people get hysterical without any jokes lol - bit of physiology for you:angry: laughing releases endorphins and encephalins [the natural opioids - morphine-like substances] in your body, so you feel happy even in these tough times - now I am laughing cos I am happy for you!! :lol:

Coming to the point, yes @Glockity is q right [except I am not sure why he/she has an abbreviation for "litre" at the end].

So,
Diameter = 4 X 10^-7/2400 m
................= 4000 X 10^-10/2400 m
................= 1.67 X 10^-10 m

ALWAYS QUICKLY CHECK YOUR ANSWER, yeah? [we are reducing the value of 4 X 10^-7 by a factor of about 1/4 of 10000, agreed? - (1/4 of 10000 is 2500) [simple mental maths, which you will need if by chance you are doing the UCAT exam for medicine] - so dividing the thickness of foil by 10000 gives about 4 X 10^-11 then multiplying by 4 gives 16 X 10^-11, which is nearly exactly the same as the answer in bold - yippee!! Ok sorry, now your belly is in agony - lol even more: sorry!! :sorry:

Be safe!
M.

wait wheres the litre abbreviation
Reply 4
Original post by macpatgh-Sheldon
Hi good to see you are laughing - my grandad [in India] goes to a laughing club where people get hysterical without any jokes lol - bit of physiology for you:angry: laughing releases endorphins and encephalins [the natural opioids - morphine-like substances] in your body, so you feel happy even in these tough times - now I am laughing cos I am happy for you!! :lol:

Coming to the point, yes @Glockity is q right [except I am not sure why he/she has an abbreviation for "litre" at the end].

So,
Diameter = 4 X 10^-7/2400 m
................= 4000 X 10^-10/2400 m
................= 1.67 X 10^-10 m

ALWAYS QUICKLY CHECK YOUR ANSWER, yeah? [we are reducing the value of 4 X 10^-7 by a factor of about 1/4 of 10000, agreed? - (1/4 of 10000 is 2500) [simple mental maths, which you will need if by chance you are doing the UCAT exam for medicine] - so dividing the thickness of foil by 10000 gives about 4 X 10^-11 then multiplying by 4 gives 16 X 10^-11, which is nearly exactly the same as the answer in bold - yippee!! Ok sorry, now your belly is in agony - lol even more: sorry!! :sorry:

Be safe!
M.

Thank you!!!! x
Reply 5
Original post by Glockity
so 2400 atoms are 4x10^-7 m thick therefore 1 atom would be (4x10^-7) / 2400 I think.

It says to round to 3.s.f- what would i put for that?
Original post by lol9812
It says to round to 3.s.f- what would i put for that?

1.67 X 10^-10 m - what this guy said, 3 sigfigs is the first three digits along with the x10^-10
Reply 7
Original post by Glockity
1.67 X 10^-10 m - what this guy said, 3 sigfigs is the first three digits along with the x10^-10

okay thanks x
Original post by Glockity
wait wheres the litre abbreviation


Sorry but there seems to be an "l" at the end of the line [after /2400], is there not?
Original post by macpatgh-Sheldon
Sorry but there seems to be an "l" at the end of the line [after /2400], is there not?

thats an i think but i capitalised
Original post by Glockity
thats an i think but i capitalised

Omg - apologies @Glockity, I must have skimmed through your post rather hurriedly and misread your sentence.

I hope you have not taken the undeserved insult to your knowledge of SI units to heart! :frown:
Original post by macpatgh-Sheldon
Omg - apologies @Glockity, I must have skimmed through your post rather hurriedly and misread your sentence.

I hope you have not taken the undeserved insult to your knowledge of SI units to heart! :frown:

oh its fine lol

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