To determine the mass of atom, find the molar mass of one-atomic substance, using Mendeleyev's table. Then divide this weight into Avogadro's number (6.022•10^(23)). It will also be the mass of atom, in those units in which molar weight was measured. The mass of atom of gas is through its volume which is easy for measuring.
It is required to you
- For determination of mass of atom of substance take Mendeleyev's table, a roulette or a ruler, the manometer, the thermometer.
Instruction
1. Determination of mass of atom of a solid body or liquid For determination of mass of atom of substance, define its nature (of what atoms it consists). Find a cell in which the corresponding element is described in Mendeleyev's table. Find the mass of one of this substance in grams on a moth who is in this cell (this number corresponds to the mass of atom in atomic units of mass). Divide the molar mass of substance into 6.022•10^(23) (Avogadro's number), the mass of atom of this substance in grams will be result. It is possible to determine the mass of atom and in a different way. For this purpose taken in Mendeleyev's table increase the atomic mass of substance in atomic units of mass by number 1.66 • 10^(-24). Receive the mass of one atom in grams.
2. Determination of mass of atom of gas In case in a vessel there is a gas of the unknown nature, determine its weight in grams, having weighed an empty vessel and a vessel with gas, and find the difference of their masses. After that measure vessel volume by means of a ruler or a roulette, with the subsequent performing calculations or other methods. Express result in cubic meters. Measure by the manometer gas pressure in a vessel in pascals, and take its temperature the thermometer. If the scale of the thermometer is graduated in degrees Celsius, define value of temperature in Kelvins. For this purpose to value of temperature on a scale of the thermometer add number 273.
3. For determination of mass of a molecule of gas increase the mass of this volume of gas by its temperature and number 8.31. Divide result into the work of pressure of gas, its volume and Avogadro's number 6.022•10^(23) (m0=m•8.31•T/(P·V·NA)). The mass of a molecule of gas in grams will be result. In case it is known that a gas molecule diatomic (gas not inert) divide the turned-out number into 2. Having multiplied result by 1.66•10^ (-24) it is possible to receive its atomic mass in atomic units of mass and to define a chemical formula of gas.