1g of hydrogen contains 6x10^23 atoms. the atomic wt. of helium is 4 u. it follows that the number of atoms in 1g of He is:
1÷4×6×10^23
See your posts above.
To find the number of atoms in 1g of He, we need to calculate the number of moles of He in 1g, and then multiply it by Avogadro's number.
Step 1: Calculate the number of moles of He.
We know that the atomic weight of He is 4 u. 1 mole of any substance contains Avogadro's number of atoms, which is 6x10^23 atoms.
To find the number of moles, we divide the mass of He by its atomic weight:
Moles of He = Mass of He / Atomic weight of He
Since we are given 1g of He, we have:
Moles of He = 1g / 4 g/mol
Moles of He = 0.25 mol
Step 2: Calculate the number of atoms in 1g of He.
Now, we multiply the number of moles of He by Avogadro's number:
Number of atoms in 1g of He = Moles of He * Avogadro's number
Number of atoms in 1g of He = 0.25 mol * 6x10^23 atoms/mol
Number of atoms in 1g of He = 1.5x10^23 atoms
Therefore, there are approximately 1.5x10^23 atoms in 1g of helium.
To find the number of atoms in 1g of helium, you can use the Avogadro's number and the atomic weight of helium.
1) Determine the molar mass of helium:
The atomic weight of helium is given as 4 u. The molar mass is the same but in grams, so 1 mole of helium weighs 4 grams.
2) Find the number of moles in 1g of helium:
Given that 1g of helium is used, you divide the mass by the molar mass:
n = mass / molar mass
n = 1g / 4g/mol
n = 0.25 mol
3) Calculate the number of atoms in 0.25 mol of helium:
Using Avogadro's number (6 x 10^23 atoms/mole), multiply it by the number of moles:
Number of atoms = Avogadro's number x number of moles
Number of atoms = 6 x 10^23 atoms/mol x 0.25 mol
Number of atoms = 1.5 x 10^23 atoms
Therefore, there are approximately 1.5 x 10^23 atoms in 1g of helium.