To effectively separate different components of a mixture on a chromatography column, a difference in Rf value of at least is necessary. A. 0.1 B. 0.2 C. 0.4 D. 0.8

0.1

Explanation:

The retention factor is the ratio of distance traveled by sample to distance traveled by solvent. Its values range between 0-1. Zero means that the solvent is too nonpolar and its polarity must be reduced. An Rf of 1 means that the solvent is too polar and its polarity must be decreased. Two substances must differ in Rf at least by 0.1 to be effectively separated by chromatography.

the only liquid elements at standard temperature and pressure are bromine (br) and mercury (hg). although, elements caesium (cs), rubidium (rb), francium (fr) and gallium (ga) become liquid at or just above room temperature.

explanation:

each  column  of the  table  is called a group. elements in a group share similar properties. groups are  read  from  top  to  bottom. metal. metalloid. nonmetal. solid. liquid. gas. fe. hg. o.  2. 3. 4. 5. 6. 7. 8. 9.  2. beryllium. 9.012. 4.  sodium. 22.990.  11. 3.  magnesium. 24.305.  12.  potassium. 39.098.  19. 4.  calcium. 40.078.  20. i guess  i