Please help! Molarity of HCl: 0.300 1. Exact molarity (M) of HCl tirant used? 2.
ID: 484630 • Letter: P
Question
Please help! Molarity of HCl: 0.300
1. Exact molarity (M) of HCl tirant used?
2. Moles of Ca?
3. Moles of HCl?
4. Ratio of mol HCl to Ca
5. Round ratio
6. From my experimental results, what is the formula of calcium hydroxide product from the reaction?
Please show work
Titration Data: Final Buret reading (mL): 19.52mL 20.95mL Initial Buret reading (mL: 0.00mL 0.00mL Net vol. of HCl titrant (mL): 5.48mL 4.05mL Exact molarity (M) of HCl titrant used: Calculations: moles of Ca moles of HCl ratio of mol HCl/mol Ca Round ratio of mol HCl/mol Ca to the nearest integer; From the experimental results, what is the formula of calcium hydroxide product from the reaction? One mole of HCl reacts with one mole of hydroxide (OH Show calculations:Explanation / Answer
Ans. Trial 1:
Given,
Exact molarity of HCl solution = 0.300 M
Volume of HCl used = 5.48 mL = 0.00548 L ; [1 L = 1000 mL]
#1. Moles of HCl = Molarity x volume (in L)
= 0.300 M x 0.00548 L
= (0.300 mol/ L) x 0.00548 L ; [M = mol/ L]
= 0.001644 moles
Since, 1 mol H+ (from HCl) neutralizes 1 mol OH- (from calcium hydroxide)-
number of moles of OH- = number of moles of HCl
Hence, number of moles of OH- = 0.001644 moles
#2. No correlation is provided between moles of HCl and Ca or moles of HCl and OH-; so, relative moles of HCl and Ca can’t be calculated from available data.
However, to proceed ahead, I proceed with the theoretical/ expected moles of Ca in this trial.
Let the number of moles of calcium you calculated to be 0.00080 mol.
So,
Moles of Ca = 0.00080 mol
#3. Ration (mol of HCl / Mol of Ca) = 0.001644 mol / 0.00080 mol = 2.05
#4. Round off to nearest integer = 2
#5. From the reaction, it is concluded that –
I. 1 mol HCl neutralizes 1 mol OH-
II. HCl : Ca ratio of 1:2 indicates that 1 mol Ca neutralized by 2 mol HCl. Since, calcium donates OH that actually participates reaction, 1 mol Ca contains 2 mol OH.
III. Or, since 1 mol Ca contains 2 mol OH- in its molecular formula, 1 mol calcium hydroxide requires 2 mol HCl to get neutralized.
IV. Thus, 1 mol Ca has 2 mol OH- in its molecular formula.
Thus, the molecular formula of calcium hydroxide = Ca(OH)2
Trial 2: Please get the exact moles of Calcium from your experiment or as told to you or using the molarity of Calcium hydroxide solution, etc. Proceed ahead as done for trial 1.