Question

how much thermal energy is LOST while cooling a 10g block of aluminum form 120 celcius to 80 celcious

Answer 1

\[\Delta Q = m*c*\Delta T\]

Answer 2

locate c, the specific heat of aluminum, on a table... use units for mass that agree with the units of the value you have for specific heat...

Answer 3

is the specific heat for aluminum 0.920 J/(g c)? is that what ur asking for?

Answer 4

sure.

Answer 5

do you want me to google that in order to verify that it's the correct value or something?

Answer 6

ok so i take that and i multiply it by the mass which is 10g but how do i find the delta t?

Answer 7

from 120 to 80 is a change of?

Answer 8

and if u want u can google it i have it on my homework worksheet though

Answer 9

40 degrees

Answer 10

+40?

Answer 11

i think so

Answer 12

if you had 6 twenties in your wallet and then you checked again in a few minutes and you only had 4 twenties, what happened?

Answer 13

you lost 40 dollars

Answer 14

120 -> 80 is a change of -40

Answer 15

so it would be negative 40?

Answer 16

yes:)

Answer 17

ok so the formula would be 5*0.920J*-40 then i would get my answer?

Answer 18

it's 10 grams

Answer 19

oh sorry i was looking at the
wrong problem lol

Answer 20

so its -368 J

Answer 21

sure but the question asks how much heat is lost... so if I asked you how much money you lost in the earlier example... what would you say?

Answer 22

-40 dollars? or 40 dollars?

Answer 23

negative 40

Answer 24

"I lost negative forty dollars"

does anyone ever say that?

Answer 25

"lost" means "negative".

Answer 26

no lol so we would say we lost 40 thermal energy?

Answer 27

temperature decreased -> heat was lost....
delta T is negative delta Q is negative
delta Q = -386 J means 386 J was lost

Answer 28

oooh ok thank you!!!