What is the magnitude of total charge of all the electrons in 2.4 l of liquid water?

Im going to give you the process in such a way that you get the answer and it will be very easy. What you need here is the formula  n = N x m / W
N = Avagadro's number,
m = mass  
W =  molecular weight
So the process will be like this:
 n = 6.07 x10^27 x 2.4 / 18
Use your calculator and then you will have your answer