One mole of a substance contains 6.02 x 10²³ molecules.The atomic number of Li is 3 and the atomic mass is approximately 7.If you have three moles of Li,how many grams does it weigh? A)9 B)21 C)7 x 6.02 x 10²³ D)3 x 6.02 x 10²³

Question

Quizplus · Accepted Answer

To calculate the weight of 3 moles of Li, we need to first find the molar mass of Li which is approximately 6.94 g/mol (since atomic mass is approximately 7). Then we can calculate the weight of 3 moles of Li as:
Weight = 3 moles x 6.94 g/mol = 20.82 g ≈ 21 g (rounding to the nearest whole number)
Therefore, the answer is B.

One Mole of a Substance Contains 6