When a measured cell voltage is negative, the electrode to which the red lead is attached is actually the anode rather than the cathode (i. e., you should enter a positive voltage). The anode is the electrode at which oxidation takes place, so it is surrendering electrons to the external circuit. For the two cells involving the iron and copper species, the Cu(II)/Cu(s) couple is the anode. Which of the following half-cell reactions is taking place at the Cu electrode in the anode compartment of these two cells?b. Cu(s) -> Cu2+(aq) + 2e-c. Cu(s) -> Cu2-(aq)-2ed. None of above

Which statement describes covalent bases? they have hydroxide ions. they produce hydrogen ions. they are often amines. they are named the same as ionic compounds.

Lab reagent, hypothesis test.a reference solution used as a lab reagent is purported to have a concentration of 5 mg/dl. six samples are taken from this solution and the following concentrations are recorded: (5.32, 4.88, 5.10, 4.73, 5.15, 4.75) mg/dl.these six measurements are assumed to be an srs of all possible measurements from solution.they are also assumed to have a standard deviation of 0.2, a normal distributin, and a mean concentration equal to the true concentration of the solution.carry out a significance test to determine whether these six measurements provide reliable evidence that the true concentration of the solution is actually not 5 mg/dl.

Answer asap : ( a. how does mucus prevent the entry of pathogens? b. describe two ways white blood cells protect us from pathogens.