Questions: Refer to a periodic table and tell how many helium atoms (He) would be needed to get close to the same mass as an average oxygen atom (O).
six
four
twelve
one-fourth
Transcript text: Refer to a periodic table and tell how many helium atoms $(\mathrm{He})$ would be needed to get close to the same mass as an average oxygen atom ( O ).
six
four
twelve
one-fourth
Solution
Solution Steps
Step 1: Determine the Atomic Mass of Helium and Oxygen
The atomic mass of helium (He) is approximately 4.0026 atomic mass units (amu), and the atomic mass of oxygen (O) is approximately 16.00 amu.
Step 2: Calculate the Ratio of Oxygen to Helium Mass
To find out how many helium atoms are needed to match the mass of one oxygen atom, we calculate the ratio of the atomic mass of oxygen to that of helium:
\[
\text{Ratio} = \frac{\text{Atomic mass of oxygen}}{\text{Atomic mass of helium}} = \frac{16.00}{4.0026} \approx 4.000
\]
Step 3: Determine the Number of Helium Atoms Needed
The ratio calculated in Step 2 indicates that approximately 4 helium atoms are needed to have a mass close to that of one oxygen atom.