Histidine has three ionizable functional groups. write the equilibrium equations for its three ionizations and assign the proper pka for each ionization. draw the structure of histi- dine in each ionization state. what is the net charge on the his- tidine molecule in each ionization state?

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

a  solution  is always transparent, light passes through with no scattering from solute particles which are molecule in size. the  solution  is homogeneous and does not settle out. a colloid is intermediate between asolution  and a  suspension. while asuspension  will separate out a colloid will not.