Researchers who study microbial degradation of vinyl chloride (vc) use small sealed glass bottles to keep vc from partitioning into the room air during experiments. once, while i was working in a lab, a new master’s student walked up to me to show me that her sealed bottle was open (true story). after the seal broke the bottle contained 3 mg of vinyl chloride in 60 ml of water. assume the volume of air in the lab equaled 100 m3 and that there was no ventilation (luckily that was not true), the temperature and pressure in the lab were 25 0c and 1 atm, respectively. in addition, henry’s law constant equals 26.8 l×atm mole . • compare the equilibrium concentration of vc in the air to the 3-h air quality standard of [vc]std = 10 ppmv. • what should the new master’s student have done, when she noticed the seal on the bottle that contained vc was open?

Astudent made a graph plotting the progress of a reaction over time. the student forgot to label the y-axis of the graph. a graph is shown with two graph lines. one graph line starts at a higher position on the y axis and slopes downwards towards the right. the other graph line starts at a lower position on the y axis and slopes upwards towards the right. the two graph lines stop short of intersecting each other and continue as separate lines which gradually become straight and parallel to the x axis. a vertical line is shown at a point where the two graph lines finally became parallel to the x axis. this vertical line is labeled equilibrium. the title on the x axis is time and an arrow pointing towards the right is shown above time. the title on the y axis is left blank. what best explains the label that the student should use on the y-axis? amount, because as the amount of product decreases, the amount of reactant increases over time. reaction rate, because forward and backward reaction become equal at equilibrium. amount, because the amounts of reactants and products become constant after equilibrium is reached. reaction rate, as the rate of forward reaction increases and rate of backward reaction decreases over time.