Question

4, Question Details Solid sodium phosphate is added to an aqueous solution of manganese(II) nitrate in a series of experiments. The salts react to form a precipitate according to the chemical equation 2 Na3PO4(aq) 3 Mn(NO3)2(aq)Mn3(PO4)2(s) 6 NaNO3(aq) In each experiment, the precipitate was collected, dried, and weighed Exp 1 Exp 2 Exp 3 Exp 4 Exp 5 Exp 6 Volume of manganese) 487.6 m nitrate Mass of sodium phosphate g Mass of precipitate 377.6 ml 323.7 mL 232.4 mL 184.6 mL 122.4 mL 10.820 g 10.820 9 10.820 g 10.820 g 10.820 g 10.820 9 11.827 g 11.825 9 11.825 g 11.827 g 10.525 g 6.977 g Identify the limiting reagent in each experiment. sodium phosphate manganese(lI) nitrate manganese(Il) phosphate sodium nitrate B. Experiment 2: sodium phosphate O manganese(II) nitrate O manganese(Il) phosphate sodium nitrate C. Experiment 3: sodium phosphate manganese(II) nitrate O sodium nitrate D. Experiment 4 sodium phosphate O manganese(I) nitrate O manganese(lI) phosphate sodium nitrate E. Experiment 5: manganese(II) nitrate O manganese(Il) phosphate Osodium nitrate F. Experiment 6 sodium phosphate O manganese(I) nitrate O manganese(II) phosphate sodium nitrate Submit Answer

Answer 1

Limiting reagent is the reagent which is completely used up during the reaction and so the reaction cannot proceed further. In all the experiments done above, the amount of sodium phosphate taken is the same. The only thing that varies is the amount of manganese(Il) nitrate.

Molar mass of sodium phosphate is 163.94 g/mol. Let us calculate the number of moles of the reactants.

metes Hence number여nates a+Na3PO42-10.3203- 63.94 glmot available-40g the 의eaction Dse taimula 一.. No 4-metes : Given neight Malah mass Novd, sinte in the abeve equaion, we can see that 2 molescq Nasrat setures 3 rates o Mn(N0s)2 ·to que-one mete 여 Mng(P04),. Hence 0.066 notes Na3P0+ nould He pire. 0.099 metes a舌hing (PO)2 fasi conplete ae choon Thiu means that in all the6 expesiment Non a asume that-1M-aqueous-solution 118.95me Ths means that it 178.S M aqueous solutien So 1 Arnt af Mo Nay-No.ofnefeed-Mnaara ulable ㅡ 여 Mn(No. , p dissolved in 1000mL-Hould- ?' Expt-4232.4 ml o.232 mol E/p

As we can see in all of the experiments (1-6) there is excess of manganese nitrate to react with 0.066 moles of sodium phosphate. Hence in all the 6 cases sodium phosphate is being completely used up and hence acts as the limiting reagent.