Sarah spilt a bottle of ammonia in one corner of the laboratory. Soon the whole laboratory was filled up with pungent irritating order. The students immediately opened the doors and windows and switched on the exhaust fans. After some time, the students got relief. - State the values of the fellow students and teacher in the above accident. - Suggest any precaution which is needed in the laboratory.

Astable electron arrangement for an atom is one that does not easily change. how is this arrangement arrived at? a. valence electrons are transferred or shared to create a full outer shell of electrons. b. valence electrons are discarded into space to create a full outer shell of electrons. c. protons (positive charge) pair with valence electrons (negative charge) to create a strong bond. d. outer shells with valence electrons are transferred or shared.