1
$\begingroup$

Which would produce the largest change in the $\ce{H2O}$ level when added to water in a $\pu{25 mL}$ graduated cylinder?

(A) $\pu{10.0 g}$ of $\ce{Hg}$ $(d = \pu{13.6 g/mL})$
(B) $\pu{7.42 g}$ of $\ce{Al}$ $(d = \pu{2.70 g/mL})$
(C) $\pu{5.09 g}$ of iron pyrite $(d = \pu{4.9 g/mL})$
(D) $\pu{2.68 g}$ of oak $(d = \pu{0.72 g/mL})$

I approached this question by dividing the mass by density to find the volume change. Thus, I got the answer (D), but the answer is (B).

Can anyone please explain this?

| improve this question | | | | |
$\endgroup$
0
$\begingroup$

Because it’s density is less than 1, the oak floats.

Therefore it displaced less than its full volume; some of the floating oak is above water.

Since it’s 2.68g of oak, it displaces only the volume equivalent to 2.58g of water.

| improve this answer | | | | |
$\endgroup$
0
$\begingroup$

Because oak has a density less than water (1g/mL), it won't be fully submerged. For substances more dense than water, they will be fully submerged so you don't have to worry about it. See this video to calculate how much of the oak will be submerged.

| improve this answer | | | | |
$\endgroup$

Not the answer you're looking for? Browse other questions tagged or ask your own question.