How many uranium atoms are there in 9.5 g of pure uranium? The mass of one uranium atom is 4 × 10−26 kg
To find the number of uranium atoms in 9.5 g of pure uranium, we need to use the mass of one uranium atom and Avogadro's number.
Step 1: Calculate the mass of one uranium atom in grams:
The mass of one uranium atom is 4 × 10^-26 kg. We need to convert this to grams by multiplying it by 1000 since there are 1000 grams in one kilogram.
Mass of one uranium atom in grams = (4 × 10^-26 kg) × 1000 = 4 × 10^-23 g
Step 2: Calculate the number of moles of uranium in 9.5 g of pure uranium:
We can use the molar mass of uranium to convert grams to moles. The molar mass of uranium is approximately 238 g/mol.
Number of moles of uranium = Mass of uranium / Molar mass
Number of moles of uranium = 9.5 g / 238 g/mol = 0.04 mol
Step 3: Calculate the number of uranium atoms:
One mole of any substance contains Avogadro's number of particles, which is approximately 6.022 × 10^23 particles/mol.
Number of uranium atoms = Number of moles of uranium × Avogadro's number
Number of uranium atoms = 0.04 mol × 6.022 × 10^23 atoms/mol = 2.409 × 10^22 atoms
Therefore, there are approximately 2.409 × 10^22 uranium atoms in 9.5 g of pure uranium.
To find the number of uranium atoms in 9.5 g of pure uranium, we can use the formula:
Number of atoms = (mass of substance / molar mass) * Avogadro's number
First, we need to convert the mass of one uranium atom from kilograms to grams:
Mass of one uranium atom = 4 × 10^(-26) kg = (4 × 10^(-26)) * 1000 g = 4 × 10^(-23) g
Next, we calculate the molar mass of uranium (U) from the periodic table. The molar mass of uranium is approximately 238 g/mol.
Now we can substitute the values into the formula:
Number of atoms = (9.5 g / 238 g/mol) * (6.022 × 10^23 atoms/mol)
Calculating this equation gives:
Number of atoms = (9.5 / 238) * (6.022 × 10^23) ≈ 2.4 × 10^22 uranium atoms
Therefore, there are approximately 2.4 × 10^22 uranium atoms in 9.5 g of pure uranium.
convert 4 × 10−26 kg to grams by multiplying by 1000
(9.5 g of pure uranium)(1 atom/___g uranium atom)
notice the grams cancel out and all you're left is the unit atom