World Nature Conservation Day 2021

 

Happy Guru Purnima to everyone 24 July 2021

 

DAILY LOG 23 JULY 2021

 CLASS VIII 

CLASSWORK - CHAPTER-6 Making salts was discussed 

HOMEWORK - Try to do workbook questions of  Topic-1 Chapter-6 

CLASS VII 

CLASSWORK - Chapter-2 Effects of lifestyle on health was discussed 

HOMEWORK - Research on Type-1 and 2 Diabetes for discussion in class  

Happy Eid-ul-adha

 

CLASS VII ASSEMBLY DISCUSSIONS

 

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Science Activity - PAPER CHROMATOGRAPHY

PAPER CHROMATOGRAPHY 

• APPARATUS REQUIRED 
• black and blue mark­ers
• Sanitizer
• sheet of thick pa­per
• beaker
• 
  

• PROCEDURE

Take a small sheet of thick paper which can fit in a beaker. Make dots on the pa­per withblack, blue, and a mix­ture of col­ors (black + blue). To make the dots on the same lev­el, draw a start­ing line with a pen­cil first. Now low­er the pa­per in the beaker with ethanol, about half a cen­time­ter from the bot­tom. Then seal the beaker, so the ethanol doesn’t evap­o­rate. Af­ter half an hour, ob­serve the move­ment and sep­a­ra­tion of col­ors on the pa­per.

Chro­matog­ra­phy is a method for an­a­lyz­ing sub­stances by their sep­a­ra­tion into com­po­nents. The method was dis­cov­ered by Mikhail Tsvet, who sep­a­rat­ed col­or pig­ments of plants. In our ex­per­i­ment, we must se­lect the sol­vent which is con­tained the mark­ers. This is usu­al­ly ethanol.

Due to the cap­il­lary ef­fect, the ethanol soaks the pa­per even­ly, tak­ing the dyes with it. The dyes in the mix­ture re­act dif­fer­ent­ly with the al­co­hol, so they rise at dif­fer­ent speeds.

Sep­a­ra­tion is based on this dif­fer­ence in speed.