Mole Bridge HW 5-3

HW 5-3 #1 1 mole 12 g 0.25 moles 0.50 moles 0.33 moles 0.75 moles 3.0 g4.0 g 6.0 g 9.0 g

HW 5-3 # moles 2.50 moles 3.00 moles 24 g 18 g 36 g

How to Use the Mole Bridge Two conversion factors: 1 mole 1 mole 1 mole x atomic mass (g) x atomic mass (g)

The Actual Bridge over River Mole or “under”

Example: What is the mass in grams of 9.34 moles of Fe? 9.34 mol Fe 9.34 mol Fe (55.8 g Fe) (1 mole Fe) = 521 g 3 Sig Fig Note: SF of final answer should match SF of original given (Molar Mass SF should have at least as many SF as given).

HW 5-3 Part 1 moles → grams 1) What is the mass in grams of MOLES of Ni (atomic #28)? 1) What is the mass in grams of MOLES of Ni (atomic #28)? mol Ni (1 mole Ni) (58.69 g Ni) = 30.6 g

HW 5-3 Part 1 moles → grams 2) What is the mass in grams of 2.49 moles of SO 3 ? SO mol SO 3 (1 mole SO 3 ) (80.07 SO 3 g) = 199 g S: 1 x 32.07= O: 3 x 16.00= g/mol

HW 5-3 Part 2 grams → moles 3) 3) 26.2 g Au (1 mole Au) ( g Au) = mol

HW 5-3 Part 2 grams → moles 4 ) What is the number of moles in grams of ethanol, C 2 H 5 OH? C 2 H 5 OH g C 2 H 5 OH C 2 H 5 OH (1 mole C 2 H 5 OH) C 2 H 5 OH (46.08 g C 2 H 5 OH) = g C 2 : 2 x 12.01= H 6 : 6 x 1.01 = 6.06 O: 1 x 16.00= g/mol

HW 5-3 Part 3 moles → atoms or molecules 5) 5) moles Cu (6.022 x atoms Cu) (1 mole Cu) = 9.0 x atoms Cu

HW 5-3 Part 3 moles → atoms or molecules 6) 1.25 x moles Pb(CH 3 CO 2 ) 2 (6.022 x molecules) (1 mole Pb(CH 3 CO 2 ) 2 ) = 7.53 x molecules Pb(CH 3 CO 2 ) 2

HW 5-3 Part 3 moles → atoms or molecules 6) x atoms Se (6.022 x atoms) (1 mole Se ) = moles Se

How many ATOMS are present in g of Bi? g Bi g Bi ( g Bi) (1 mole Bi) (6.022 x atoms Bi) (1 mole Bi) = x atoms Bi

How many MOLECULES are present in 6.37 g of CO? 6.37 g CO 6.37 g CO (28.01 g CO) (1 mole CO) (6.022 x molecules CO) (1 mole CO) = 1.37 x molecules CO C: 1 x 12.01= O: 1 x 16.00= g/mol

What is the mass in grams of x atoms of Zr? x atoms Zr (91.22 g Zr) (1 mole Zr) = g Zr (6.022 x atoms Zr)

What is the mass in grams of 4.03 x molecules of C 6 H 6 ? 4.03 x molecules C 6 H 6 (78.12 C 6 H 6 g) (1 mole C 6 H 6 ) = 52.3 g C 6 H 6 (6.022 x molecules C 6 H 6 ) C 6 : 6 x 12.01= H 6 : 6 x 1.01= g/mol

How many C atoms and H atoms are present in 10 molecules of methane, CH 4 ? C: 1 C: 1 H: 4 H: 4

How many C atoms and H atoms are present in 10 molecules of methane, CH 4 ? C: 10 C: 10 H: 40 H: 40

How many C atoms and H atoms are present in 1000 molecules of methane, CH 4 ? C: 1000 C: 1000 H: 4000 H: 4000

How many C atoms and H atoms are present in x molecules of methane, CH 4 ? C: x C: x H: 4 (6.022 x ) = x H: 4 (6.022 x ) = x 10 24

How many C atoms and H atoms are present in x molecules of methane, CH 4 ? C: x C: x H: 4 C atoms/molecules (7.089 x molecules) = x H: 4 C atoms/molecules (7.089 x molecules) = x 10 24