Question

A Glass rod is also called as:
A. Stirring rod
B. Stir rod
C. Both A and B
D. None of these

Answer 1

Hint: Think about what a glass rod is. In the laboratory, one of the most basic tools is a glass rod which serves a lot of purposes. Think about which processes we make use of a glass rod and then see the options and determine which one is the apt term for a glass rod.

Complete step by step answer:
A glass rod is one kind of equipment in Laboratory. It is made up of solid glass with rounded ends. Generally glass rods are made of Pyrex glass (chemically known as borosilicate glass). This used to accelerate the mixing of chemicals and liquids.
‘Stir’ is to mix something, hence ‘Stir rod’ is apt.
Stirring is the process, so ‘Stirring rod’ is also correct.
So, the correct answer is “Option C”.

Additional Information:
Glass rod is used for stirring because of its stable chemical properties. As glass rod can withstand high temperature and has resistance towards acid and alkali, it is preferred to use glass rod for mixing solutions.
Some advantages of glass rod are:
Corrosion resistance - The glass forms like quartz can resist acid and alkali. The quartz does not react with any acid, except hydrofluoric acid. Pyrex is also inert to many chemicals which are used in normal laboratories.
Strong hardness - A glass rod is very hard because of which it meets the requirements of laboratory and industry.
High working temperature - The soda-lime glass rod can work in $400{}^\circ C$ temperature and the best quartz glass rod can work in $1200{}^\circ C$ temperature continuously.
Small thermal expansion - Stirring rods have small thermal expansion that is, they do not break at high temperature.

Applications of glass rod
- Stirring: It is used for mixing of the chemicals and liquid.
- Electrification equipment: Positive and negative electricity can be easily determined by rubbing fur or silk on glass rod which generates static electricity.
- Glass rods are used to decant a liquid slowly by controlling flow rate and giving direction to the liquid to flow. This helps to avoid spillage and helps to determine accurate results.
- Glass rods are also used to spread substances like silica gel on glass plates or foil during TLC. Glass rod can be used as a spreader.

Note: Borosilicate glass is a kind of glass with silica and boron trioxide as the main glass – forming constituents. This glass has a property of low thermal expansion i.e. having low tendency of matter to change its shape, area and volume in response to a change in temperature.