Respuesta :
The average that reflect the typical ratio of natural abundance of iron isotope is the atomic weight of the iron. Iron has four stable isotope that is iron 54 ,56, 57, 58. its atomic weight by mass is 9.27 x10^-22 grams
therefore number of atoms in cm^3 is
(7.87g/cm^3)/(9.27x10^-22)=8.49x10^21atoms/cm^3
therefore number of atoms in cm^3 is
(7.87g/cm^3)/(9.27x10^-22)=8.49x10^21atoms/cm^3
Answer: The number of iron atoms in given amount is [tex]8.49\times 10^{22}[/tex]
Explanation:
Density of a substance is defined as the ratio of its mass and volume. The chemical equation representing density of a substance is:
[tex]\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}[/tex]
We are given:
Density of iron = [tex]7.87g/cm^3[/tex]
Volume of iron = [tex]1cm^3[/tex]
Putting values in above equation, we get:
[tex]7.87g/cm^3=\frac{\text{Mass of iron}}{1g/cm^3}\\\\\text{Mass of iron}=(7.87g/cm^3\times 1cm^3)=7.87g[/tex]
To calculate the number of moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]
Given mass of iron = 7.87 g
Molar mass of iron = 55.65 g/mol
Putting values in above equation, we get:
[tex]\text{Moles of iron}=\frac{7.87g}{55.65g/mol}=0.141mol[/tex]
According to mole concept:
1 mole of an element contains [tex]6.022\times 10^{23}[/tex] number of atoms.
So, 0.141 moles of iron will contain = [tex]0.141\times 6.022\times 10^{23}=8.49\times 10^{22}[/tex] number of atoms.
Hence, the number of iron atoms in given amount is [tex]8.49\times 10^{22}[/tex]