Preparation and Reactions of Boric Acid
Experiment 6
Preparation and reactions of boric acid
Objectives:
To prepare boric acid from sodium tetraborate (borax)
To carry out tests on the prepared sample of boric acid
To study the physical and chemical properties of boric acid
Introduction:
Boron is an element in the p-block of the periodic table. It has the electron configuration of 1s22s22p1 and is in group 3 or goup 13 (IUPAC classification). In nature, it consists of two isotopes 10B (19.6%) and 11B (80.4%).
Boron is bonded to the oxygen in nature. The important sources of Boron are borax and kernite. Boron oxides and their derivatives are technologically important and are relatively inexpensive to produce. Boron oxides is very difficult to crystallise and normally exists in a glassy state (d=1.83gcm-1). Molten boron oxide has a high melting point of 450 degree celcius that is readily dissolves metal oxides to form coloured borate glasses as one of the main commercial uses of boric oxide. Particularly, borosilicate glasses find wide applications in glassblowing and the production of glass objects. On top of the boric acid, it is also known as hydrogen borate as a weak monobasic Lewis acid. At room temperature, it exists as white powder or colourless crystals with a chemical formula of H3BO3 or B(OH)3.
Apparatus and materials:
•Sodium tetraborate
•Concentrated hydrochloric acid
•Concentrated sulphuric acid
•Methyl red indicator
•Mannitol
•Beaker
•Methanol
•Distilled water
•Electric heater
•Ice
•Test tube
•Test tube rack
•Glass rod
•Suction funnel
•Suction pump
•Filter flask
•Filter paper
•Spatula
•Watch glass
•Splint
Procedures:
1. About 10g of sodium tetraborate (borax) is dissolved in 40cm3 of water in a beaker.
2. The mixture is boiled and 5cm3 of concentrated hydrochloric is added into the solution.
3. The beaker is immersed into a container with ice and water to cool down the temperature.
4. After the solution is cooled down, the boric acid is
Preparation and reactions of boric acid
Objectives:
To prepare boric acid from sodium tetraborate (borax)
To carry out tests on the prepared sample of boric acid
To study the physical and chemical properties of boric acid
Introduction:
Boron is an element in the p-block of the periodic table. It has the electron configuration of 1s22s22p1 and is in group 3 or goup 13 (IUPAC classification). In nature, it consists of two isotopes 10B (19.6%) and 11B (80.4%).
Boron is bonded to the oxygen in nature. The important sources of Boron are borax and kernite. Boron oxides and their derivatives are technologically important and are relatively inexpensive to produce. Boron oxides is very difficult to crystallise and normally exists in a glassy state (d=1.83gcm-1). Molten boron oxide has a high melting point of 450 degree celcius that is readily dissolves metal oxides to form coloured borate glasses as one of the main commercial uses of boric oxide. Particularly, borosilicate glasses find wide applications in glassblowing and the production of glass objects. On top of the boric acid, it is also known as hydrogen borate as a weak monobasic Lewis acid. At room temperature, it exists as white powder or colourless crystals with a chemical formula of H3BO3 or B(OH)3.
Apparatus and materials:
•Sodium tetraborate
•Concentrated hydrochloric acid
•Concentrated sulphuric acid
•Methyl red indicator
•Mannitol
•Beaker
•Methanol
•Distilled water
•Electric heater
•Ice
•Test tube
•Test tube rack
•Glass rod
•Suction funnel
•Suction pump
•Filter flask
•Filter paper
•Spatula
•Watch glass
•Splint
Procedures:
1. About 10g of sodium tetraborate (borax) is dissolved in 40cm3 of water in a beaker.
2. The mixture is boiled and 5cm3 of concentrated hydrochloric is added into the solution.
3. The beaker is immersed into a container with ice and water to cool down the temperature.
4. After the solution is cooled down, the boric acid is