Answer Happy

Today's Lab In this activity, you will be given a vial with a mixture of copper (II) chloride and sodium phosphate tribasic dodecahydrate. Each group will receive a mixture; note that the ratio of copper (II) chloride to sodium phosphate is different for each group. The unbalanced equation is written below: CuCl2 (aq) + Na3PO4 (aq) → Cu3(PO4)2 (s) + NaCl (aq) Sodium phosphate tribasic is presented as a solid dodecahydrate. We will be assuming that the precipitate forms as a trihydrate. Thus, the overall chemical equation for the reaction is: CuCl2 (aq) + Na3PO4•12 H20 (aq) → Cu3(PO4)2*3 H20(s) + NaCl (aq) Use the following molar masses when performing stoichiometric calculations: CuCl2 = 134.45 g/mol Na3PO4•12 H2O = 380.12 g/mol Cu3(PO4)2•3 H20 = 434.63 g/mol.

Day 1 - Data 1/1 points Enter your data: Unknown mixture sample ID: D Enter A, B, C, or D Total mass of unknown mixture used: 0.98 g Mass of filter paper: 0.71 g Evaluate Extra Info Data accepted.

Day 1 - Observations 2/2 points In which test tube did you observe the formation of a precipitate during step 12 of the procedure? In rare cases, you may not have observed the formation of a precipitate in either test tube. If this is the case, please consult with your instructor. Test tube in which a precipitate formed: B Enter A or B Which was the limiting reactant in your unknown sample mixture? Na3PO4 Enter CuCl2 or Na3PO4 (format matters) Evaluate Your observations are consistent with your unknown mixture sample ID. Ensure you understand the reason why this is the limiting reactant. Try explaining the reason to your partner.

Day 2 - Data 2/2 points Enter your data: Mass of filter paper + precipitate: 0.915 g Mass of precipitate: 0.205 g Moles of precipitate: 4.71e-4 mol Evaluate Extra Info Data accepted.

Results 0/3 points Enter your results: Mass of limiting reactant in your unknown mixture: g Mass of excess reactant in your unknown mixture: g Mass percent of the limiting reactant in your unknown mixture: % Evaluate Extra Info Check your limiting reactant calculation. Did you balance the chemical equation for the reaction? Are you using the correct molar mass?