Answer:
a. 94 g of Mn
b. 0.239 g of He
c. 6.69ₓ10⁻⁸ g of N
d. 1.14ₓ10⁻⁶ g of U
Explanation:
This is the way to make the conversions:
Number of atoms → Moles of element → grams
We begin from the information that: 1 mol of atoms has 6.02×10²³ (NA) atoms
Let's convert all the numbers to amount of moles (number of atoms / NA)
a. 1.03 x 10²⁴ of Mn / 6.02×10²³ = 1.71 moles of Mn
b. 3.60 x 10²² of He / 6.02×10²³ = 0.0598 moles of He
c. 2.88 x 10¹⁵ of N /6.02×10²³ = 4.78ₓ10⁻⁹ moles of N
d. 2.88 x 10¹⁵ of U /6.02×10²³ = 4.78ₓ10⁻⁹ moles of U
We convert the moles to mass (moles . molar mass)
a. 1.71 moles of Mn . 54.94 g /1mol = 94 g of Mn
b. 0.0598 moles of He . 4 g /1mol = 0.239 g of He
c. 4.78ₓ10⁻⁹ moles of N . 14 g /1mol = 6.69ₓ10⁻⁸ g of N
d. 4.78ₓ10⁻⁹ moles of U . 238.03 g /1mol = 1.14ₓ10⁻⁶ g of U
