Answer:
[tex]\boxed {\boxed {\sf 0.282 \ mol \ Cl}}[/tex]
Explanation:
The molar mass, or mass of 1 mole of a substance, is used to convert grams to moles. We are given the molar mass of chlorine. It is 35.45 grams per mole.
We convert using dimensional analysis, so we must set up a conversion factor using the molar mass.
[tex]\frac { 35.45 \ g \ Cl}{1 \ mol \ Cl}[/tex]
We are converting 10.0 grams of chlorine to moles, so we must multiply the conversion factor by this value.
[tex]10.0 \ g \ Cl* \frac { 35.45 \ g \ Cl}{1 \ mol \ Cl}[/tex]
Flip the conversion factor. The result is equivalent and allows us to cancel the units of grams of chlorine.
[tex]10.0 \ g \ Cl* \frac {1 \ mol \ Cl}{ 35.45 \ g \ Cl}[/tex]
[tex]10.0 * \frac {1 \ mol \ Cl}{ 35.45 }[/tex]
[tex]\frac {10.0 }{35.45} \ mol \ Cl[/tex]
[tex]0.282087447 \ mol \ Cl[/tex]
The original value of grams (10.0) has 3 significant figures, so our answer must have the same. For the number we found, that is the thousandth place. The 0 in the ten-thousandth place tells us to leave the 2 in the thousandth place.
[tex]0.282 \ mol \ Cl[/tex]
Approximately 0.282 moles of chlorine are in 10.0 grams of chlorine.
