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69 solutions

Mass Percent

Q. 9. What is the percent composition by mass (to one decimal place) of oxygen and hydrogen in 1 mol of water?

Solved • Sep 13, 2019

Mass Percent

Q. If 15% of the body mass of an 81 kg adult consists of TG’s, what is the total available fuel reserve, in kJ and kcal, in the form of TG’s? • Assume energy value of TG’s = 37.4 kJ/g • 1 kJ = 0.239 kcal

Solved • Sep 15, 2019

Mass Percent

Q. A 2.350x10^-2 M solution of a NaCl in water is at 20.0 degrees C. The sample was created by dissolving a sample of NaCl in water and then bringing the volume up to 1.000 L. It was determined the volume of water needed to do this was 999.4 mL. The density of water at 20.0 degrees C is 0.9982 g/mL. Calculate the concentration of the salt solution in percent by mass. Express your answer to four significant figures and include the appropriate units.

Solved • Sep 9, 2019

Mass Percent

Q. 3.00 g of an unknown lead II salt is reacted with excess BaSO4 solution. 2.745 g of PbSO4 is precipitated. What is the mass percent of lead II in the unknown salt?

Solved • Sep 8, 2019

Mass Percent

Q. 9.780-g gaseous mixture contains ethane and propane. Complete combustion to form carbon dioxide and water requires 1.120 mol of oxygen. Calculate the mass percent of ethane in the original mixture

Solved • Sep 2, 2019

Mass Percent

Q. An aqueous solution of 6.70 M ammonia, NH3, has a density of 0.950 g/mL. The percent by mass of NH3 in the solution is ____ %.

Solved • Aug 30, 2019

Mass Percent

Q. The mole fraction of magnesium sulfate, MgSO4 in an aqueous solution is 3.10 x 10^-2. The percent by mass of magnesium sulfate in the solution is ___ %.

Solved • Aug 30, 2019