A dye known as bromothymol blue appears yellow under some conditions and blue under others, as shown in the following equation

HB(aq) <--> H+(aq) + B-(aq)

yellow_blue

Which chemical would contribute a common ion if added to this system?

CaCl2

NaF

H2SO4

K2SO4

How do we find the answer?

The kinetic energy of the liquid increases. hope this !

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.