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*finished the test its B* In a science lab, a student heats up a chemical from 10 °C to 25 °C which requires thermal energy of 30000 J. If mass of the object is 40 g, the specific heat capacity of the chemical would be

Group of answer choices


100 J /g* °C


50 J /g* °C *its this one*


75 J /g* °C


25 J /g* °C

User Fazal
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1 Answer

2 votes

Answer:

Yup! The answer is 50 J/g* °C

Step-by-step explanation:

I also took the test but I know how to work out the problem for anyone who wants to know how to solve it.

Remember the formula q = m*C*ΔT

m = the mass in grams

C = the specific heat Capacity

ΔT = change in time

q = amount of energy

So, find out what was given and what we need to look for:

m = 40 g

C = ?

ΔT = we're heating up (the temperature increases) a chemical so it needs to be a positive number. 25 - 10 = 15 °C

q = 30000 Joules

Now, set up the equation:

q = m*C*ΔT

30000 = 40 * C * 15

Multiply 40 and 15 to get 600:

30000 = 600 * C

Divide both sides by 600 to get C by itself (plug this into your calculator):

30000/600 = 600 * C/600

You are left with 50 = C

Now, you just need to plug in the units to get B. 50 J/g* °C

I hope I helped clear up any confusion! :D

User RaeX
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