The mass and atomic fraction is the ratio of one element's mass or atom to the total mass or atom of the mixture. The concentration of H2O2, expressed as a weight-weight percent, can be determined by titration with a standard solution of potassium permanganate. Nitric Acid Composition. given O2 = 22400 cm3 This compound is also known as Hydrogen Peroxide. Mass percent composition describes the relative quantities of elements in a chemical compound. 4. Molar mass of H2O2 = 34.01468 g/mol. Convert the change in volume from Activity1 to liters. Convert the air temperature from Activity 1 from Celsius to Kelvin. 0 0. bushmaker. (ii) How many moles of oxygen were produced at the end of the decomposition? The percent composition can be found by dividing the mass of each component by total mass. Mass percent composition is also known percent by weight. It is abbreviated as w/w%. The molar mass of hydrogen peroxide is 34.01 g/mol. Calculate the moles of hydrogen peroxide present in each trial. Convert grams H2O2 to moles or moles H2O2 to grams. of water vapor and oxygen gas, which equals the mass of the hydrogen peroxide present in the initial OxiClean sample. 2. The percent composition is used to describe the percentage of each element in a compound. Lv 4. Find the mass of each individual element and then divide by the total molecular weight. How many moles of oxygen gas are formed from the decomposition of 3 moles of hydrogen peroxide… Its long calculation to do it here but this video will help. (iii) Use your answer to (ii)to calculate the concentration, in mol/dm3, of the 50.0cm3 of aqueous hydrogen peroxide used in the experiment. Molecular weight calculation: 1.00794*2 + 15.9994*2 ›› Percent composition by element Percent Composition of Oxygen = 48.00/63.02. For a solution, mass percent equals the mass of an element in one mole of the compound divided by the molar mass of the compound, multiplied by 100%. Hydrogen peroxide (H2O2, 34.02 g/mol) is a chemical compound which is often used in hair bleach. 0 0. josh. 3. 1 decade ago. A chemist pipets a 10.00 mL aliquot of a liquid hair bleach, which has a density of 1.1081 grams mL-1, into a flask. Percent Composition Calculator. Thus, the percent composition of water, by mass, is #11.19%# hydrogen and #88.81%# oxygen… 4 years ago. 5. Problem: Hydrogen peroxide (H2O2) decomposes into water and oxygen gas. Calculate the moles of oxygen generated in each trial. [At room temperature and pressure one mole of oxygen occupies 24000cm3.] Source(s): For water we have to calculate it % of Oxygen and % of Hydrogen. hydrogen peroxide → oxygen + water 2H 2 O 2 (aq) → O 2 (g) + 2H 2 O(l) The volume of oxygen given off can be measured using a gas syringe, or by collecting in an inverted measuring cylinder. (i) To calculate the mass of H2O2 in 1 litre of 2 M solution: Moleuclar mass of H2O2 = 2 x 1 + 2 x 16 = 34 amu Now 1 litre of 1 M solution contains H2O2 = 34 g(ii) To calculate the volume of O2 liberated at STP from 1000 cm3 of 2M solution: Decomposition of H2O2 can be represented as: Now 68 g of at S.T.P. Answer link.