Question

7.34g of metal A changes in temperature from 41.4°C to 54.7°C and
absorbs 923.5J in the process. Calculate the specific heat of metal A

Answer 1

Answer:

9.46 J/g °C

General Formulas and Concepts:

Chemistry

Thermodynamics

Specific Heat Formula: q = mcΔT

• q is heat (in J)
• m is mass (in g)
• c is specific heat (in J/g °C)
• ΔT is change in temperature (in °C or K)

Math

Pre-Algebra

Order of Operations: BPEMDAS

1. Brackets
2. Parenthesis
3. Exponents
4. Multiplication
5. Division
6. Addition
7. Subtraction

• Left to Right  

Equality Properties

1. Multiplication Property of Equality
2. Division Property of Equality
3. Addition Property of Equality
4. Subtraction Property of Equality

Explanation:

Step 1: Define

Identify variables

[Given] m = 7.34 g

[Given] q = 923.5 J

[Given] ΔT = 54.7 °C - 41.4 °C = 13.3 °C

[Solve] c

Step 2: Solve for c

1. Substitute in variables [Specific Heat Formula]:                                       923.5 J = (7.34 g)c(13.3 °C)
2. Multiply:                                                                                                         923.5 J = (97.622 g °C)c
3. [Division Property of Equality] Divide 97.622 g °C on both sides:             9.45996 J/g °C = c
4. Rewrite:                                                                                                            c = 9.45996 J/g °C

Step 3: Check

Follow sig fig rules and round. We are given 3 sig figs as our lowest.

9.45966 J/g °C ≈ 9.46 J/g °C

Topic: AP Chemistry

Unit: Thermodynamics

Book: Pearson AP Chemistry