Fill a clean mayonnaise or pickle jar one-half full with soybeans. Add fine textured sand. Shake the jar until the beans and sand are evenly distributed and the contents fill the jar to the top. Place the jar on a pan at the front of the class. At the start of class, ask students to present hypotheses as to what will happen when the contents are completely saturated with water. List the predictions on the board. Fill the jar with water as you collect the student hypotheses. Use warm water to speed the process. Within 30 to 45 minutes, expect the glass to crack due to the build up of osmotic pressure caused by the seeds’ imbibition of water.

How does decreasing the gas volume affect the pressure of a gas?

Using a value of ksp = 1.8 x 10-2 for the reaction pbcl2 pb+2(aq) + 2cl -(aq). if the value of ksp was determined to be only 1.2 x 10-2: too much solid has dissolved. additional precipitate is forming. the solution is unsaturated. the ions are now combining to reduce their concentrations.

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.