How is the number of moles of an element determined from a known mass? A. The known mass is multiplied by Avogadro's number to get moles.
B. The known mass is divided by Avogadro's number to get moles.
C. The atomic number is used as a conversion factor to convert
grams to moles.
D. The mass of 1 mole of the element is used as a conversion factor
to convert grams to moles.

Which statement justifies that phosphine (ph3) is a polar molecule?

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.

What metric units would you use to measure the thickness of a key