When preparing standard molar solutions,concentration on the volumes and quantities of solutions used should be properly taken into consideration.It is highly significant that a chemist knows the exact concentration of a particular solution. This can be achieved by making a standard solution of the compound in question.
Now considering how this substances are been related, it is fundamental that a standard chemical reaction or equation which shows the relationship between the amount of reactant and the product formed is represented.
A given mass of a particular substance with a known molecular formula can be transformed directly and become standard with its mole intact or theoretically determined. The mole is the amount of a substance which contains as many elementary entities such as atoms, molecules and ions as there are contain in 12g of Carbon-12.
Now considering how a standard solution is been prepared, firstly a solution with a known and accurate concentration is termed a standard solution.For example, a solution that contains 22g of sodium chloride in 1 dm3 of a solution is a standard solution.
In the preparation of a standard solution of sodium hydroxide of 0.1M Concentration, which we shall discussed in this article, the apparatus used are : Volumetric flask of 1000ml capacity, wash bottle,distilled water, a beaker with a pipe, glass funnel, chemical balance, or any other convenient balance.
In the lab, what you will do is to weigh a wash glass and weight out, into it 4g of sodium hydroxide pellets (this should be done quickly to avoid the absorption of water from the atmosphere) because it is deliquescent. Transfer the sodium hydroxide into a beaker of 250cm3 capacity containing distilled water. Now carefully wash down the wash flask with a jet of distill water from the watch bottle and allow the washings to drop into the beaker.
This is to ensure that no part of the sodium hydroxide is left behind in the wash bottle or glass. Use the glass stirng rod to stire the solution carefully to ensure that all the solid sodium hydroxide dissolves.
Transfer the solution into the volumetric flask using the glass funnel containing about 500ml of distilled water . use distilled water to rinse the inside of the beaker at least twice and the glass siring and pour the washings into the measuring flask.
Shake the flask gently. Fill it up with distill or possibly deionize water up to actual mark,then add more distill water drop by drop after removing the funnel and rinsing it properly till the lowest level of the meniscus is on the mark when at the eye level .
Lock the stopper on the flask and shake very well. The solution prepared is 0.1M sodium hydroxide.