What is the mass (in grams) of 7.98 moles of krypton (Kr)?

• A. 669 g
• B. 319 g
• C. 228 g
• D. 7.98 g

Answer: (A)

Verified step by step guidance

1. Identify the given quantity and what is asked: You have 7.98 moles of krypton (Kr) and need to find the mass in grams.
2. Recall the relationship between moles, molar mass, and mass: \(\text{mass} = \text{moles} \times \text{molar mass}\).
3. Find the molar mass of krypton (Kr) from the periodic table. The molar mass is the atomic mass expressed in grams per mole (g/mol).
4. Multiply the number of moles (7.98 mol) by the molar mass of krypton to calculate the mass in grams.
5. Write the final expression for mass: \(\text{mass} = 7.98 \; \text{mol} \times \text{molar mass of Kr} \; (\text{g/mol})\) and solve to get the mass.