The standard atomic weight is the average mass of an element in atomic mass units ("amu"). Though individual atoms always have an integer number of atomic mass units, the atomic mass on the periodic table is stated as a decimal number because it is an average of the various isotopes of an element.
Answer:
Explanation:
70% (vol/vol) means
cotnaimns 70 %(vol/vol) 70 ml of isoprapnol is there in 100 ml of Rubbing sold alcohol.
if it is 200 ml then obvouly it has the 70*2 =140 ml of isoproanol required.
Answer:
Explanation:
There are three types of interactions involved between the particles when solution are formed.
1 : Solute - solute interaction:
2 : Solute - solvent interaction:
3 : Solvent - solvent interaction:
1 : Solute - solute interaction:
It is the inter-molecular attraction between the solute particles.
2 : Solute - solvent interaction:
It involve the inter-molecular attraction between solvent and solute particles.
3 : Solvent - solvent interaction:
It involve the intermolecular attraction between solvent particles.
Solutions are formed if the intermolecular attraction between solute particles are similar to the attraction between solvent particles.
Exothermic process:
The process will exothermic when solute solvent bonds are formed with the release of energy and energy required to brake the solute-solute particles and solvent solvent particles are less.
Endothermic process:
The process will be endothermic when energy required to break the solute-solute particles and solvent solvent particles are higher than energy released when solute solvent bonds are formed .
You can tell the difference by How shiny it is and by how heavy it is