Answer:
The number of moles HBr = 0.001825
The concentration of Ca(OH)2 = 0.009125 M
Explanation:
Step 1: Data given
Volume of the Ca(OH)2 = 100.0 mL = 0.100 L
Molarity of HBr = 5.00 * 10^-2 M
Volume of HBR = 36.5 mL = 0.0365 L
Step 2: The balanced equation
Ca(OH)2 + 2HBr → CaBr2 + 2H2O
Step 3: Calculate molarity of Ca(OH) 2
b*Va* Ca = a * Vb*Cb
⇒with b = the coefficient of HBr = 2
⇒with Va = the volume of Ca(OH)2 = 0.100 L
⇒with ca = the concentration of Ca(OH)2 = TO BE DETERMINED
⇒with a = the coefficient of Ca(OH)2 = 1
⇒with Vb = the volume of HBr = 0.0365 L
⇒with Cb = the concentration of HBr = 5.00 * 10^-2 = 0.05 M
2 * 0.100 * Ca = 1 * 0.0365 * 0.05
Ca = (0.0365*0.05) / 0.200
Ca = 0.009125 M
Step 4: Calculate moles HBr
Moles HBr = concentration HBr * volume HBr
Moles HBr = 0.05 M * 0.0365 L
Moles HBr = 0.001825 moles