hello I need help with problem number three part A and B thank you




In letter A, we have to find out the number of moles of NaOH from the given volume, which must be in Liters, and also the given concentration, which is 1.00 M of NaOH
The volume found was = 5.625 mL, which in liters will be 0.00562 Liters
The formula we must use is:
n = M * V
n = 1.00 * 0.00562
n = 0.005625 moles of NaOH
In letter B, we have to calculate the moles that are in excess of HCl, the reaction that we have is:
NaOH + HCl -> NaCl + H2O
We have:
0.005625 moles of NaOH
0.0150 moles of HCl
According to the molar ratio between NaOH and HCl, we have a ratio of 1 mol of NaOH for 1 mol of HCl, therefore:
1 NaOH = 1 HCl
0.005625 NaOH = x HCl
x = 0.005625 moles of HCl
0.0150 - 0.005625 = 0.009375 moles of HCl of excess