Question

We know copper is a transition metal that can show a +1 or +2 ionic charge. In this lab, we will use the ideas of limiting and excess reactants to determine what copper does in a really neat reaction.

The reaction we will explore today is between copper and silver (I) nitrate. Since we don’t know the charge of copper, we will write two separate reactions and by doing stoichiometry calculations we should be able to determine which reaction actually occurred

Write the two balanced equations for this reaction, one with copper taking on a +1 charge and the other with copper taking on a +2 charge.  

Lab data:

Initial Mass of copper: 1.85g

Initial Mass of Silver Nitrate:1.54g

Write out clear calculations for determining the limiting reactant and calculating the amount of excess reactant expected from each reaction.

Answer 1

Limiting reagent: Гла reactout conica is totally Consumed in the reaction is called limiting reagoutor) Linciting reactant. Exc Rя reactaut:- The reactant cwrich is left after reaction is called Excese veactant. Copper being ΜΟΥe reactive displaces silver from silver Nitrete solution. Copper taking tchause in the reaction- Cet AS NO3 → cue (NO3) + AS copper (I) Nitrele. Imole of ca reacts will Imole of ASNO 3 to form i mole ct Cu(NO3) and Imole of As. Imole of cu Imole CAS NO 3 required, 63.59 of cu 170 9 of As Nog rereeired, 1.85 9 of cu -> ?? Maar of AgNO3 required a 1-85 X170 63.5 4.959

4.95 9 of Agnoz required. But 1.54 st AS NO3 is only present ire AgNO, is present elan resuired. AgNO3 is totally less Courtered in the reaction, AgNO3 is limiting reagent . Copper is Excess reactant. Imole ct AgNO3 Imole of ca resuired. 10 9 ct AgNO3 63.5 3 ot cu reseived. 1.54 s ct AS NO 3 ? 1 Mars of cu resuired a 1:54 x 63,5 9 120 - 0.5753 0.515 8 of ce resuired. But 1.85 g ot Copper is present. le copper is Excess reactant. Copper is Excess by : (1.85 -0.575) 9 1.2753 1-275 3 of copper is lett excess after reaction.

copper taking +2 charge: + 2Ag NOZ Cu(NO3)2 +2 Ag copper (I) nitrete. Imole ct Copper reacts will amore ct ASNO, to tovu Imole of ce(NO3)2 aud 2uole c} Ag. zuole at AS NO₃ required inole of cel 63.5 g of cel (2x170) S of AS NOZ required, 1.85 s otce ? 1 required a 1.85 x 2X 170 AS NO3 Mar 8 ) S 63.5 2 9.905 3

But 1.54 9 of AS NO is only prereut. Thay required AgNO3 is present less ie AS No3 is limitius reactant. Copper is Excess reactaut. 340 3 of AgNO3 → 63.5 g ut ca required. 1.54 8 of AgNO3 -22 Ma88 со си үсешто - 1.54 x 63.5 340 lo 0.287 3 Copper is Excess by (1.85-0-287) 9 1-5633 is left after reactica 1.5638 of Copper