Question

how many moles of silicon are in 245 g of silicon? a. 8.72 mol b. 28.0 mol c. 1.10 × 10-1 mol d. 6.90 × 103 mol

Answer 1

Atomic mass silicon = 28.085 u

1 mol Si ---------------- 28.085 g  
?  ------------------------ 245 g

245 x 1 / 28.085 => 8.72 mol

answer A

Answer 2

Answer:

The answer to How many moles of silicon are in 245 g of silicon? is:

a. 8.72 mol

Explanation:

To resolve this problem, we need to know the Silicon atomic weight, we can find this information in  the periodic table of elements

$Si= 28.0855 \frac{g}{mol}$

This means that for every mole, there are 28.0855 grams of Silicon

Now, with this information we can find the answer to this problem:

$245 g*\frac{1 mol}{28.0855 g} = 8.72 mol of Silicon$