In a lava lamp, a waxy substance rises and falls repeatedly. What causes the waxy substance to rise?

A) The waxy substance is cold.
B) The waxy substance is warm.
C) The waxy substance is less dense than the surrounding liquid.
D) The waxy substance is more dense than the surrounding liquid. Convection is occurring.

A100 kmol/h stream that is 97 mole% carbon tetrachloride (ccl4) and 3% carbon disulfide (cs2) is to be recovered from the bottom of a distillation column. the feed to the column is 16 mole% cs2 and 84% ccl4, and 2% of the ccl4 entering the column is contained in the overhead stream leaving the top of the column. calculate the mass and mole fractions of ccl4 in the overhead stream, and determine the molar flow rates of ccl4 and cs2 in the overhead and feed streams. 12. mw_ccla- 153.82; mw_cs2-76.14.