Dilute aqueous hydrogen peroxide is used as a bleaching agent and for disinfecting surfaces and small cuts. its concentration is sometimes given as a certain number of "volumes hydrogen peroxide," which refers to the number of volumes of o2 gas, measured at stp, that a given volume of hydrogen peroxide solution will release when it decomposes to o2 and liquid h2o. how many grams of hydrogen peroxide are in 0.125−l of 20 "volumes hydrogen peroxide" solution

7.62 grams.

According to the question, 0.125 L of the 20 "volumes hydrogen peroxide" solution would decompose to produce of oxygen gas.

The question indicates that the volume of here is measured under STP, which means that every of gas would have a volume of . There would thus be of molecules in the 2.5 L of produced.

It takes two moles of hydrogen peroxide to produce one mole of oxygen. The unknown solution must contain 0.224 mol of hydrogen peroxide to produce all the 0.112 mol of oxygen.

Hydrogen peroxide has a formula mass of , meaning that each mole of it would have a mass of 34.02 grams. 0.224 mol of would thus have a mass of

most historians agree that gabriel mouton, the vicar of st. paul’s church in lyons, france, is the “founding father” of the metric system. he proposed a decimal system of measurement in 1670. mouton based it on the length of one minute of arc of a great circle of the earth (now called a nautical mile, 1852 meters). he also proposed the swing-length of a pendulum with a frequency of one beat per second as the unit of length (about 25 cm). a pendulum beating with this length would have been fairly easy to produce, thus facilitating the widespread distribution of uniform standards. over the years, his work was revised, improved, and extended by a number of french scientists.

the political sponsor of weights and measures reform in the french revolutionary national assembly was the bishop of autun, better known as talleyrand. under his auspices, the french academy appointed several committees to carry out the work of developing a usable system of weights and measures for france. one of the committees recommended a decimalized measurement system based upon a length equal to one ten-millionth of the length of a quadrant of the earth’s meridian (i.e., one ten-millionth of the distance between the equator and the north pole).