Question

missed this? watch kcv: the mole concept, iwe: the mole concept - converting b read section 6.3. you can click on the review link to access the section in your etext. calculate the mass in grams of each elemental sample: part a 1.27×10²⁰ uranium atoms m = g submit request answer part b

Explanation:

Step1: Find moles of U atoms

Avogadro's number is \(6.022\times10^{23}\) atoms/mol. Moles (\(n\)) = number of atoms / Avogadro's number.
\(n = \frac{1.27\times10^{20}\text{ atoms}}{6.022\times10^{23}\text{ atoms/mol}} \approx 2.11\times10^{-4}\text{ mol}\)

Step2: Calculate mass using molar mass

Molar mass of U is 238.03 g/mol. Mass (\(m\)) = moles × molar mass.
\(m = 2.11\times10^{-4}\text{ mol} \times 238.03\text{ g/mol} \approx 0.0502\text{ g}\)

Answer:

\(0.0502\) (or more precise: ~0.0502 g, depending on significant figures)