How to test the chemicals in lab?

 Testing of Chemicals:

The Chemical Change are the cause of formation of new chemical including molecules and compounds. I'm telling to my student about how to test the chemicals and what are the method of recognizing the chemical. Specially Acid , Base and the Salt. I have collected the chemical sample of acid , base and salt in the separate beaker. I manage the indicator Viz; Red Litmus paper, Blue Litmus paper, Methyl Orange, and the Phenolphthalein as an Indicator. I told student to make the separate group and make the table on the practical copy to report the chemical changes. Student are told to do practical group by group.

                             Red litmus paper and Blue litmus paper is tested directly by putting it into the solution of acid ,base and the salt. The changes is noticed directly and is noted. In the case of Methyl Orange and Phenolpthalein indicator, the solution are tested in the test tube. After testing one solution in test tube, it is washed properly by the water to avoid the fault in the chemical testing. The testing is made several time by the student to observe the chemical changes.

Here are some of the chemical changes noted during the chemical testing:

	Indicator	Acid	Base	Salt
	Blue litmus paper	Red color appear	--------------	-------------------
	Red litmus paper	--------------	Blue color appear	-------------------
	Methyl Orange	Red	Yellow	-------------------
	Phenolphthalein	colorless	Pink	--------------------
Some reaction are edible like citric acid, acetic acid etc. Some acid are also present in the fruits like apple contain juice contains malic acid and sour milk consists of the lactic acid. Acid is sour in test where as strong acid are highly corrosive and very dangerous for the naked skin. Some gases like carbon dioxide are acidic in nature. Carbon dioxide reacts with water to give Carbonic Acid which is a weak acid. Moist Litmus Paper if placed in gas jar containing Carbon dioxide , it changes the Blue color of litmus paper into Red. Also the Moist Red litmus paper if placed in the gas jar containing ammonia gas, then it converts into the blue color because the water molecule in the paper reacts with ammonia to forms ammonium hydroxide, which is the weak base. 1) Carbon dioxide is collected by the downward displacement of carbon dioxide gas. Carbon dioxide are heavier gas than air. So it get settled down when passes inside the gas jar and air are displaced outside. 2) Ammonia is collected by the downward displacement of the air from the gas jar which is upside down. Since ammonia is lighter than Ammonia , so it prefer to goes up in the Gas jar. The air inside the gas jar then displaced outside the gas jar. In this way Ammonia is collected inside the gas jar.                         It is non combustible and also not the supporter of combustion. But it supports the burning magnesium ribbon to burns producing the dazzling light. Also ammonia is basic in nature. It is sparingly soluble in nature. It became basic hydroxide when dissolve in water.

 

Enable GingerCannot connect to Ginger Check your internet connection
or reload the browserDisable in this text fieldEditEdit in GingerEdit in Ginger×Enable GingerCannot connect to Ginger Check your internet connection
or reload the browserDisable in this text fieldEditEdit in GingerEdit in Ginger×Enable GingerCannot connect to Ginger Check your internet connection
or reload the browserDisable in this text fieldEditEdit in GingerEdit in Ginger×Enable GingerCannot connect to Ginger Check your internet connection
or reload the browserDisable in this text fieldEditEdit in GingerEdit in Ginger×Enable GingerCannot connect to Ginger Check your internet connection
or reload the browserDisable in this text fieldEditEdit in GingerEdit in Ginger×