For each of the following circumstances, indicate whether the calculated molarity of NaOH would be lower, higher or unaffected. Explain your answer in each case.
a.the inside of the pipet used to transfer the standard HCI solution was wet with water.
b.You added 40mL of water to the titration flask rather than 25mL
c.The buret, wet with water, was not rinsed with NaOH solution before filling the buret with NaOH solution.
d.Five drops of phenolphthalein were added to the solution to be titrated rather than 3 drops.
arent they all supposed to be affected but the last one?
b won't make a difference. One more of those listed won't make a difference. The others will. The problem asks you, not if they will be affected, but if the results will be high or low.
Ohhh, so which one would be lower, higher, or unaffected. Can you pleaseeeeeeeeeeeeee explain
For each of the following circumstances, indicate whether the calculated molarity of NaOH would be lower, higher or unaffected. Explain your answer in each case.
a.the inside of the pipet used to transfer the standard HCl solution was wet with water.
mols HCl = L x M
If pipet had water, then we transferred too little HCl; i.e., L is too small which will make mols HCl smaller than we think. When we titrate with NaOH,
M NaOH = mols/L. We have fewer mol than we think we have, that means L NaOH will be smaller, and mols/smaller number means a higher M that we calculate for NaOH.
The others are done the same way.
You are correct, all of the given circumstances will affect the calculated molarity of NaOH, except for the last one.
a) When the inside of the pipet used to transfer the standard HCI solution is wet with water, the calculated molarity of NaOH would be lower. This is because water will dilute the concentration of NaOH added during the titration process, resulting in a lower molarity.
b) If you added 40 mL of water to the titration flask instead of the required 25 mL, the calculated molarity of NaOH would also be lower. This is because the increased volume of water will dilute the concentration of NaOH further, leading to a lower molarity.
c) If the buret, wet with water, was not rinsed with NaOH solution before filling it with NaOH solution, the calculated molarity of NaOH would be higher. The presence of water in the buret can cause dilution of the NaOH solution, resulting in a higher calculated molarity.
d) When five drops of phenolphthalein are added to the solution to be titrated instead of three drops, the calculated molarity of NaOH would be unaffected. The volume of phenolphthalein is relatively small compared to the other solution volumes, so the effect on the molarity calculation is negligible.
Overall, all the given circumstances (except for the last one) will lead to a change in the calculated molarity of NaOH.