Displaced volume:
final volume - initial volume
1 mL = 1 cm³
38.5 mL - 35.0 mL = 3.5 cm³
hope this helps!
the first is hydroxide. I believe d is the second one but I'm not 100% positive so you may want to get a second opinion
The molarity of the stock solution of luminol is 1.2 M
<u><em>calculation</em></u>
step 1: find the moles of luminol using (moles= mass/molar mass) formula
molar mass of Luminol= 177 g/mol
moles is therefore= 16.0 g/ 177 g/mol=0.0904 moles
Step 2: find the molarity using (molarity= moles/volume in liters) formula
convert Ml into liters = 75.0/1000= 0.075 L
molarity is therefore= 0.0904 moles/ 0.075 L= 1.2M
