Answer:
[tex]\boxed {\boxed {\sf 0.80 \ mol\ F}}[/tex]
Explanation:
We are asked to find how many moles are in 4.8 × 10²³ fluorine atoms. We convert atoms to moles using Avogadro's Number or 6.022 × 10²³. This is the number of particles (atoms, molecules, formula units, etc.) in 1 mole of a substance. In this case, the particles are atoms of fluorine.
We will convert using dimensional analysis and set up a ratio using Avogadro's Number.
[tex]\frac {6.022 \times 10^{23} \ atoms \ F}{ 1 \ mol \ F}[/tex]
We are converting 4.8 × 10²³ fluorine atoms to moles, so we multiply the ratio by this number.
[tex]4.8 \times 10^{23} \ atoms \ F *\frac {6.022 \times 10^{23} \ atoms \ F}{ 1 \ mol \ F}[/tex]
Flip the ratio so the units of atoms of fluorine cancel each other out.
[tex]4.8 \times 10^{23} \ atoms \ F *\frac { 1 \ mol \ F}{6.022 \times 10^{23} \ atoms \ F}[/tex]
[tex]4.8 \times 10^{23} *\frac { 1 \ mol \ F}{6.022 \times 10^{23} }[/tex]
Condense into 1 fraction.
[tex]\frac { 4.8 \times 10^{23} }{6.022 \times 10^{23} } \ mol \ F[/tex]
Divide.
[tex]0.7970773829 \ mol \ F[/tex]
The original measurement of atoms has 2 significant figures, so our answer must have the same. For the number we found, that is the hundredths place. The 7 in the thousandths tells us to round the 9 in the hundredths place up to a 0. Then, we also have to round the 7 in the tenths place up to an 8.
[tex]0.80 \ mol \ F[/tex]
4.8 × 10²³ fluorine atoms are equal to 0.80 moles of fluorine.
