Question

To measure the concentration of an aqueous solution of H.O an analytical Chemists endpoint with 72.9 ml 0.3200 Mpotassium permanganate ( 0) solution strong acid to 450 gaple of the solution and rates it to the The balanced chemical ecuation for the reactions: 6H(aq) SH..(aq) + 2Mno, Goy) - 50.6) + 2Malas) + 8H,000 What kind of reaction is this? precipitation redox XS ? you said this was a precipitation reaction enter the chemical formula of the precipitate you said this was an acid-base reaction enter the chemical formula of the reactant that is acting as the base you said this was a redox reaction enter the chemical symbol of the element that soxidized Calculate the mass percent of H., in the same. Be sure your answer has 3 significant digits

Answer 1

Answer

Type of reaction : redox

Element oxidised : O

Mass percent of H2O2 : 2.84%

Explanation

6H⁺(aq) + 5H2O2(aq) + 2MnO4^-(aq) ------> 5O2(g) + 2Mn²⁺(aq) + 8H2O(l)

O is oxidized from -1 to 0

Mn is reduced from +7 to +2

Stoichiometrically, 2moles of MnO4^- reacts with 5moles of H2O2

moles of MnO4^- consumed = (0.2200mol/1000ml)×72.9ml = 0.016038mol

moles of H2O2 present in the sample = (5/2)× 0.016038mol = 0.040095mol

mass of H2O2 in the sample = 0.040095mol × 34.02g/mol = 1.364g

mass percent of H2O2 = (1.364g/48.0g)×100 = 2.84%