MOLE RATIOS IN CHEMICAL EQUATIONS PRELAB QUESTIONS NAME When chromium metal is added to copper sulfate, there are two possible reactions: (a) Cr + CuSO4 CrSO4 Cu (b) 2Cr 3CuSO4 Cr2(SO4)3 3Cu 1. THEORETICAL RATIOS, GIVEN BY EQUATION What is the ratio of moles Cr to moles Cu shown in equation (a)? Express this ratio as a fraction, moles Cr divided by moles Cu. Do the division and express the number to three significant figures. What is the ratio of moles Cr to moles Cu shown in equation (b)? Express this ratio as a fraction, moles Cr divided by moles Cu. Do the division and express the number to three significant figures. 2. EXPERIMENTAL RATIO 1.50 g of chromium is added to a solution of CuSO4. 2.75 g of Cu were formed. Calculate moles of chromium. Calculate moles of copper. Divide moles Cr by moles Cu, expressing the ratio to three significant figures. SHOW ALL WORK. Compare to part 1. Which reaction occurred, (a) or (b)? 63

MOLE RATIOS IN CHEMICAL EQUATIONS PRELAB QUESTIONS NAME When chromium metal is added to copper sulfate, there are two possible reactions: (a) Cr + CuSO4 CrSO4 Cu (b) 2Cr 3CuSO4 Cr2(SO4)3 3Cu 1. THEORETICAL RATIOS, GIVEN BY EQUATION What is the ratio of moles Cr to moles Cu shown in equation (a)? Express this ratio as a fraction, moles Cr divided by moles Cu. Do the division and express the number to three significant figures. What is the ratio of moles Cr to moles Cu shown in equation (b)? Express this ratio as a fraction, moles Cr divided by moles Cu. Do the division and express the number to three significant figures. 2. EXPERIMENTAL RATIO 1.50 g of chromium is added to a solution of CuSO4. 2.75 g of Cu were formed. Calculate moles of chromium. Calculate moles of copper. Divide moles Cr by moles Cu, expressing the ratio to three significant figures. SHOW ALL WORK. Compare to part 1. Which reaction occurred, (a) or (b)? 63

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter4: Stoichiometry

Section: Chapter Questions

Problem 4.98PAE

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