An solution containing an unknown quantity of iron(II) being titrated according to the following reaction:
If 39 mL of the unknown iron(II) solution requires 24 mL of 0.24M solution of Potassium
permanganate to observe a persistent pink color (the end point), What is the concentration of
iron (11)?

5Fe2+ (aq) + Mn0, (aq) + 8H* (aq) — 5Fe3+ (aq)) + Mn2+ (aq) + 4H20

Astudent pours 10.0 g of salt into a container of water and observes the amount of time it takes for the salt to dissolve. she then repeats the process using the same amounts of salt and water but this time she slowly stirs the mixture while it is dissolving. the student performs the experiment one more time but this time she stirs the mixture rapidly. the dependent variable in this experiment is: time for salt to dissolve speed of stirring amount of water mass of salt