Potassium bromide, also known as KBr, belongs to the class of inorganic compounds called alkali metal bromides. These are inorganic compounds where the largest halogen atom is bromine, and the heaviest metal atom an alkali metal.
Kbr is a strong acid-base salt that has a white crystalline form and can be dissolved in water, glycerol, ethylene glycol, liquid ammonia, and hot ethanol. It is soluble in some polar organic solvents but not in acetone.
When KBr dissolves in water it dissociates into ions of potassium, k+, and bromine, Br-. These ions are then free to interact with other molecules in the solution.
KBr has a wide range of applications in optics, including infrared optical windows, beamsplitters and interferometers. It is also used in spectroscopy, for example to measure the amount of light passing through a powder sample.
The kbr boiling point is a value that shows the boiling temperature of water when a solution contains 1 mole of KBr in 1000 ml of water. The value of kb is equal to 0.512degC/m, which is a proportionality constant.
When a solute is added to a solvent the vapor pressure of the solvent decreases and the boiling point of the solvent increases. The molal freezing-point depression constant, Kf, is -1.86degC/m, and this is a good general value for the kbr boiling point.
In this case the solution has a lower vapor pressure than the pure solvent, so more heat must be supplied to raise the vapor pressure of the solution to the external atmosphere’s vapor pressure. This can be seen in the graph of DTb as shown below.