Mol - the unit of measure of amount of substance used in chemistry. In physics and life more habitual units of measure of weight and volume – grams and liters are applied. To transfer these units in a moth, there are special formulas and methods.
It is required to you
- calculator, Mendeleyev's table
Instruction
1. It is the simplest to translate in a moth if the quantity of "elementary particles" (molecules, atoms, ions, etc.) initial substance is known. For this purpose divide this quantity of particles of substance into Avogadro's number 6.022142*10+23 (10 in the 23rd degree). The number received as a result will also be number of moles. So, for example, one molecule of any substance, is 6.022142*10-23 (10 in - the 23rd degree) moths. And, on the contrary, 6.022142*10+23 (10 in the 23rd degree) molecules of substance make 1 mol.
2. If the mass of substance and its molar weight (the mass of one of this substance) is known, then for the translation in a moth divide the mass of substance into its molar weight. If weight is expressed in grams, and molar weight in gram/mol, then the result will turn out in moths. For example, the molar mass of water is 18 grams/mol. Means contains in 36 grams of water 2 asking this substance.
3. To calculate the molar mass of substance, specify its chemical formula. Then put atomic the weight of all atoms making a molecule. The received value will be the molar mass of substance expressed in gram/mol. So, for example, the molar mass of the oxygen having chemical formula O2 will be 16*2=32 grams/mol. If very exact calculations are necessary, then values of atomic weight need to be looked for in Mendeleyev's table. So, the exact atomic mass of oxygen - 15.9994 and. e. m (atomic unit of mass).
4. To translate the known volume of gas in a moth, consider that 1 mol of gas occupies (under normal conditions) volume in 22.4 liters. That is, just divide this volume of gas (in liters) into number 22.4 and receive amount of gas in moths. So, for example, in a bucket finds room about 0.5 asking air. If very high precision of calculations is necessary, then it is necessary to use values of molar volume of concrete gas. However, for the vast majority of cases the presented method suffices (distinctions appear only in the fourth decimal sign).