# Chemistry

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#1
What is the number of atoms in 12.8g of methane, CH4 solid ?
0
2 years ago
#2
You can use Avogadro's Number (6.02x10^23) and the Mass Moles and Mr Triangle to work this problem out
0
2 years ago
#3
(Original post by Ohana Tan)
What is the number of atoms in 12.8g of methane, CH4 solid ?
number of atoms could be referring to "moles" - hence the Avogadro Constant in this question since you've got the mass in grams and you'll need the molar mass of CH4

I think it'll be:

• moles = mass in grams ÷ molar mass (Mr)
• no. of atoms = moles × Avogadro Constant

= 12.8g ÷ ((12) plus (1×4))

= (12.8g ÷ 16)

= 0.8 mol × (6.02 × 10^23) - Avogadro Constant

= 4.816 × 10^23 (so approx. 4.82 × 10^23)

*** sorry if my working / answer is incorrect; just wanted to help out! ***
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#4
(Original post by reyxhh)
number of atoms could be referring to "moles" - hence the Avogadro Constant in this question since you've got the mass in grams and you'll need the molar mass of CH4

I think it'll be:

• moles = mass in grams ÷ molar mass (Mr)
• no. of atoms = moles × Avogadro Constant

= 12.8g ÷ ((12) plus (1×4))

= (12.8g ÷ 16)

= 0.8 mol × (6.02 × 10^23) - Avogadro Constant

= 4.816 × 10^23 (so approx. 4.82 × 10^23)

*** sorry if my working / answer is incorrect; just wanted to help out! ***
But it is asking number of atoms , no the molecules
0
2 years ago
#5
(Original post by Ohana Tan)
But it is asking number of atoms , no the molecules
I know and that's what I calculated for you
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