In an electrolysis experiment, a student used copper (Cu) electrodes and a Cu(NO3)2(aq) solution. The following data were collected: Time of reaction

6.55 minutes

Average current

3.752 A

Mass change of the cathode (g)

0.502 g increase

Molar mass of Cu

63.55 g/ mol

Write the half reaction for the electrochemical reaction that occurs at the cathode.
Calculate the number of Coulombs.
Calculate the number of moles of electrons transferred in this experiment. (4 pts)
If you were unable to calculate the Coulombs in Part b above, use 1663 C.
Calculate the moles of copper lost by the anode during the reaction. (4 pts) If you were unable to calculate the moles of electrons in Part c above, use 1.73 x 10-2 as the number of moles.
Calculate the molar mass of Cu.
Calculate the error for the calculated atomic mass. (2 pts) If you were unable to calculate the molar mass in Part e above, use 65.47 as the experimental molar mass of copper

What is the result of multiplying (2.5 × 1010) × (2.0 × 10-7)? a. 5.0 × 103 b. 5.0 × 10-3 c. 5.0 × 1017 d. 5.0 × 10-17

These questions are based on the attached photo. the experiment is about burning magnesium metal with oxygen. 1. write the balanced chemical equation for the reaction you are performing. 2. calculate the mass of magnesium metal used in each trial. o trial 1: o trial 2: 3. calculate the actual yield of magnesium oxide for each trial. o trial 1: o trial 2: 4. magnesium is the limiting reactant in this experiment. calculate the theoretical yield of mgo for each trial. o trial 1: o trial 2: 5. determine the percent yield of mgo for your experiment for each trial. o trial 1: o trial 2: 6. determine the average percent yield of mgo for the two trials. your company currently uses a process with a similar cost of materials that has an average percent yield of 91 percent. if the average percent yield of this process is higher than that, this could save the company money. what is your recommendation to the company? support your recommendation using your data, calculations, and understanding of stoichiometry gathered from this lab.

Which of the following is most likely true about water in chemical solutions?