# Chemistry help again please :)

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#1
I just wanted to double check that the definitions that I have written down are correct - there seems to be multiple when I search them up so I'm not sure...

Mole - The unit the amount of a substance is measured in. The number of particles needed to make 12.00g of Carbon-12

Avogadro's Constant - The number of particles that make up 1 mole of a substance
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2 months ago
#2
Almost.
A mole is just one way of measuring the amount of a substance.
Avogadro's constant is right, and is 6.02x10^23

The number of particles in 12g of Carbon-12 is 6.02x10^23 (Avogadro's constant) and this is one mole (mass/mr --> 12/12 = 1)
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#3
Almost.
A mole is just one way of measuring the amount of a substance.
Avogadro's constant is right, and is 6.02x10^23

The number of particles in 12g of Carbon-12 is 6.02x10^23 (Avogadro's constant) and this is one mole (mass/mr --> 12/12 = 1)
Ohh ok, thank you for correcting me!

I was a bit confused as these are definitions that were given by my teacher and they are different to what I had written down.
So what would the full, correct definition of mole be?

Would it be: The amount of substance that contains 6.02x10^23 particles?
And then Avogadro's Constant is exactly what I originally said?
Last edited by Anonymous -; 2 months ago
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2 months ago
#4
Not necessarily.
What Avogadro did is essentially simplify measurements when it comes to chemicals. For example, mixing 1g of potassium and 1g of iodine would not result in a complete reaction. That's because even though they weigh the same amount, there are more particles in the gram of potassium (they are smaller, denser) than in the iodine. What you need is there to be equal number of particles in each reactant. Now it would simply not be practical to try and measure each and every atom, so what do you do?

Avogadro determined the value of 'one mole' such that one mole of any substance would contain the same number of particles. Therefore, if you had one mole of potassium and one mole of iodine, you would get a complete reaction. If you convert this to grams, it would be 39g of K and 127g of I.

so A mole is simply another unit of measurement that is relative to the number of particles of the substance such that 1 mole is equal to 6.02x10^23, Avogadro's constant, which is what you stated. So a mole does not HAVE to equal Avogadro's constant.

Sorry for the long-winded answer, hopefully that helps!
Last edited by BadManNik43; 2 months ago
0
#5
Not necessarily.
What Avogadro did is essentially simplify measurements when it comes to chemicals. For example, mixing 1g of potassium and 1g of iodine would not result in a complete reaction. That's because even though they weigh the same amount, there are more particles in the gram of potassium (they are smaller, denser) than in the iodine. What you need is there to be equal number of particles in each reactant. Now it would simply not be practical to try and measure each and every atom, so what do you do?

Avogadro determined the value of 'one mole' such that one mole of any substance would contain the same number of particles. Therefore, if you had one mole of potassium and one mole of iodine, you would get a complete reaction. If you convert this to grams, it would be 39g of K and 127g of I.

so A mole is simply another unit of measurement that is relative to the number of particles of the substance such that 1 mole is equal to 6.02x10^23, Avogadro's constant, which is what you stated. So a mole does not HAVE to equal Avogadro's constant.

Sorry for the long-winded answer, hopefully that helps!
Ohh okay, thank you for taking the time to explain That's really helpful!

I think I have written the definition wrong then, as I wrote that a mole is the amount of substance that contains 6.02x10^23 particles 😬
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