The molar masses of four unknown gases are shown in the table. Molar Mass of Unknown Gases
Gas Molar Mass
A 44 g/mol
B 20 g/mol
C 30 g/mol
D 32 g/mol
Which gas is likely to have the highest rate of effusion? (4 points)

Asolid that forms and separates from a liquid mixture is called

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)

How many molecules are in 6.0 moles of methane