What is the mass percent of F in the binary compound KrF_2?

• A. 45.8%
• B. 47.4%
• C. 36.2%
• D. 57.6%

Answer: (B)

Verified step by step guidance

1. Identify the elements in the compound KrF_2, which are krypton (Kr) and fluorine (F).
2. Find the atomic masses of each element from the periodic table: krypton (Kr) has an atomic mass of approximately 83.80 g/mol, and fluorine (F) has an atomic mass of approximately 18.998 g/mol.
3. Calculate the molar mass of KrF_2 by adding the atomic mass of one krypton atom and two fluorine atoms: \(\text{Molar mass of KrF_2} = 83.80 + 2 \times 18.998\).
4. Calculate the total mass of fluorine in the compound, which is \$2 \times 18.998$ g/mol.
5. Determine the mass percent of fluorine in KrF_2 using the formula: \(\text{Mass \% of F} = \left( \frac{2 \times 18.998}{83.80 + 2 \times 18.998} \right) \times 100\%\).