Selected Answers to
Mole Conversions Worksheet
Unit 3: Chemical Reactions
#9 A) How many moles in 124.8g Ni?
LookGiven
at mole
wheel to see # of steps
Start with
Amount
This problem goes from Mass to
Moles…..
Round
to proper Sig Figs
So it is just a one-stepCalculate
problem Answer
1 molNi
= 2.126427g = 2.126g
58.69 gNi
Use relationships to plug in proper #’s
1 Mole of Nickel = 58.69g (from Pd Table)
Fill in proper units
“No Brainer” Step is that grams go on the bottom
We are going to moles, so they go on top.
124.8gNi
Unit 3: Chemical Reactions
#11 A) How many atoms in 65.2g Hg?
LookGiven
at mole
wheel to see # of steps
Start with
Amount
This problem goes from Mass
to Round
How Many…
And
to proper Sig Figs
So it is a 2-step problem
Calculate Answer
1 molHg 6.02 x 1023 atomsHg = 1.96 x1023atoms
200.59 gHg
1
molHg
Use relationships to plug in proper #’s
1 Mole of Mercury = 200.59g 23
(from Pd Table)
Fill in proper units
1 Mole of Atoms = 6.02 x 10 atoms
“No Brainer” Step is that grams go on the bottom
We need to go to moles first, so they go on top.
Then we go from Moles to the Number of Atoms
65.2gHg
Unit 3: Chemical Reactions