Question

3. When 815 Joules of heat is added to a sample of solid copper, the temperature rises

from 12.0°C to 35°C. How many grams of copper were in the sample? Specific heat of Cu
is 0.385 J/g-K.
q=MCdeltaT

Answer 1

Step-by-step explanation:

We can use the equation q = mCΔT, where q is the amount of heat transferred, m is the mass of the sample, C is the specific heat capacity of the material, and ΔT is the change in temperature.

First, we need to calculate the change in temperature, which is:

ΔT = T₂ - T₁ = 35°C - 12.0°C = 23°C

Next, we can rearrange the equation to solve for the mass of the sample:
m = q / (CΔT)

Substituting the values we have:
m = 815 J / (0.385 J/g-K × 23°C) ≈ 90.2 g

Therefore, the sample of solid copper had a mass of approximately 90.2 grams.

Answer 2

79.3

Step-by-step explanation:

We can use the formula:

q = m * c * deltaT

where:

q is the heat added to the system, which is 815 J in this case

m is the mass of the sample we want to find

c is the specific heat of copper, which is 0.385 J/g-K

deltaT is the change in temperature, which is (35 - 12) = 23°C

Plugging in the values given, we get:

815 J = m * 0.385 J/g-K * 23°C

Simplifying this expression yields:

m = 815 J / (0.385 J/g-K * 23°C)

Thus, the mass of the copper sample is:

m = 79.3 g

Therefore, there were approximately 79.3 grams of copper in the sample.