An aluminum cylinder in a physics lab had a mass of 29.7 grams. How many aluminum atoms are present in this cylinder?

___________ × 1023 Al atoms. Do NOT enter the unit and report your final answer with 3 SFs.

a mol, Avogadro's number , of Al atoms has mass of 26.98 grams

so
(29.7 / 26.98) 6.023 * 10^23

So i plugged into that calculator and got 6.630211268e23

Is that sound about right?

yes, but 3 SF you said

6.63 * 10^23

To determine the number of aluminum atoms present in the cylinder, we need to use the concept of moles and Avogadro's number.

First, we need to calculate the number of moles of aluminum in the cylinder. We can do this using the molar mass of aluminum, which is 26.98 grams/mol. The formula to calculate the number of moles is:

moles = mass / molar mass

Substituting the given values:

moles = 29.7 g / 26.98 g/mol

moles ≈ 1.1003 mol

Next, we need to convert the number of moles to atoms using Avogadro's number, which is approximately 6.022 × 10^23 atoms/mol.

number of atoms = moles × Avogadro's number

Substituting the calculated value of moles:

number of atoms = 1.1003 mol × 6.022 × 10^23 atoms/mol

number of atoms ≈ 6.625 × 10^23 atoms

Therefore, the number of aluminum atoms present in the cylinder is approximately 6.625 × 10^23 atoms.