Answer: NOT accurate, but precise.
[translation: You screwed up, but did it in style].
Explanation:
The average mass measurement is 41.95g. Compared to the actual value of 28.0 grams, the measurement is NOT accurate.
The standard deviation for the data is 0.112. Dependiong on your definition of precision, this looks relatively good. I would go for precise.
Answer:
Approximately 
.
Explanation:
Convert both volumes to standard units (that is: liters.)
.
.
Number of moles of 
initially present (in the 
solution at 
.)
.
Number of moles of 
from the titration:
.
neutralizes at a 
ratio:
.
Hence, 
.
.
Eggshells are made primarily of calcium carbonate. The acid in vinegar softens the calcium of the eggshell. Adding a little vinegar to the water when boiling eggs is an old cook’s trick that makes them easier to peel.
A link to this experiment is below in the comment box
One way of expressing concentration is by percent. It may be on the basis of mass, mole or volume. Percent is expressed as the amount of solute per amount of the solution. For this case, we are given the percent by mass. In order to solve the amount of solute, we multiply the percent with the amount of the solution.
Mass of solute = percent by mass x mass solution
Mass of solute = 0.0350 x 2.50 x10^2 = 8.75 grams of solute
