1. pretend that a store has a huge jar of pennies that weighs exactly 25 kg (25,000 g). the person who comes
closest to guessing how many pennies are in the jar wins it.
if the actual abundance of pre-1982 and post-1982 pennies in circulation is the same as the numbers
from your sample, how many "atoms” of pennium (pennies) should there be in 25,000 g jar of
pennies. show your work!
2. you have been given a new sample of the element 'pennium' (pn), and you know that this sample has 55
atoms in it and that the total mass of the sample is 155.5g. you also know that there are two isotopes of
pennium, pennium-2.5 and pennium-3.1. it is your job to figure out how many atoms (of the 55 in your
sample) are of the isotope 2.5 and how many are of the isotope 3.1.

Lem 2 the data below are for the system ethyl propyl ether (1)-chloroform (2) at 0.5 bar. use the data to answer the following questions (all questions refer to p d 0: 5 bar). a) what are the boiling points of the pure components at 0.5 bar? b) a mixture with the overall composition z1 d 0: 1 is brought to 47.6ä±c, 0.5 bar. what is the phase? c) 100 mole of a mixture with z1 d 0: 1 (state a) is mixed with 22 mole of pure ethyl propyl ether vapor (state b). the mixing takes place at 47.6 ä±c, 0.5. bar. what is the phase of the resulting mixture (state c)? if the state is a v/l mixture report the number of moles and mole fractions in each phase. d) plot the txy graph and show states a, b and c. the graph must be done by computer and should be properly annotated. ethyl propyl ether (1) - chloroform (2) at 0.5 bar t ( ä±c) x1 y1 t ( ä±c) x1 y1 42.9 0.000 0.000 49.0 0.470 0.455 43.0 0.020 0.010 49.1 0.520 0.520 43.9 0.065 0.029 48.9 0.567 0.592 45.4 0.156 0.089 48.3 0.652 0.720 46.4 0.215 0.142 47.6 0.745 0.815 47.6 0.296 0.223 46.7 0.822 0.872 48.3 0.362 0.302 45.7 0.907 0.937 48.7 0.410 0.375 44.6 1.000

Word equation for k(s) +h2o(l) yield koh (aq) + h2

Which material burns faster? metal aluminum