Concentration is a size which characterizes qualitative composition of solution. Concentration it is accepted to call amount of the dissolved substance or its weight to the total amount or mass of liquid. Thus, the major characteristics are mass and volume shares.
It is required to you
- - the mass of the dissolved substance;
- - mass of solution.
Instruction
1. A mass fraction, it is percentage concentration - it is the dimensionless size which is equal to the relation of mass of the dissolved substance to liquid lump. Most often it is expressed as a percentage for what you need to multiply the received relation on hundred. In the form of a formula the percentage concentration can be written down in the following way: ω = m in-va/m r-ra*100%. The first value is the mass of the substance, and the second – the mass of solution in general.
2. Often in a condition of tasks the percentage concentration of substance proceeding from which, it is required to find the mass of substance or mass of solution is given. To make it very simply, it is necessary to transform an initial formula only. For finding of mass of substance it will be following: m in-va = solution m * ω/100. The mass of solution can be learned as follows: divide the mass of substance into percentage concentration and increase result by hundred. Unit of measure of mass of substance and mass of solution – grams.
3. For finding of percentage concentration in case solution was received with use of crystalline hydrate, it is necessary to use other algorithm of the decision. Crystalline hydrate has structure of Me (x) (y)) *nH2O. The statement of the problem where crystalline hydrate appears, has to contain information on the mass of the crystalline hydrate and mass of solid metal-X-acid-Y. In this case percentage concentration will equal to the mass of solution increased by the molar mass of crystalline hydrate, divided into the mass of crystalline hydrate, multiplied with dry coefficient of substance and with a molar mass of waterless substance.