Calculate density A graduated cylinder

[danny411]

forgot how to calculate density

A graduated cylinder, when filled to the 40.00 mL mark with water (density 1.00g/mL)
and capped with a stopper, had a mass of 352.05 grams. The same cylinder had a rock of mass
37.40 grams placed into it and was re-filled to the 40.00 mL mark with water. The same cylinder
when stoppered (with the same stopper) now had a mass of 383.95 grams. What is the density of
the rock

37.4g/31.9ml

not sure if I am doing volume correct

 

[danny411]

is there a method to solving this?

I don't know how to get the displaced volume /

 

[Wellesley]

is there a method to solving this?

I don't know how to get the displaced volume /

You really should have posted your question https://www.physicsforums.com/forumdisplay.php?f=157" in the Homework Forum, but that's alright.

Take a look at this site: http://www.chemicalforums.com/index.php?topic=33483.0

If you still have questions, make sure you show how you got to your answer (the more work you show the easier it is to help).

 

[Integral]

If you dropped a rock into a cylinder the water level would rise. Why do you have to, or what do you mean, by refill it?

 

[Borek]

If you dropped a rock into a cylinder the water level would rise. Why do you have to, or what do you mean, by refill it?

These are two separate experiments, both start with empty cylinder.

 

[danny411]

If you dropped a rock into a cylinder the water level would rise. Why do you have to, or what do you mean, by refill it?

not sure ?

don't know how much

 

[Borek]

You take an empty cylinder, you fill it with water to the 40 mL mark. You weight it. This is your first mass.

You take an empty cylinder, you put a rock in it, you fill it with water to the 40 mL mark. You weight it. This is your second mass.