Question

A chemist places a 100 g cube of each of the metals listed in the table on a separate hot plate. Based on the specific heat values in the table, rank the metals in terms of how quickly they will reach the target temperature of 80°C. Use "1" to indicate the fastest and "5" to indicate the slowest.

Fe:
Al:
Cu:
Sn:
Pb:
A 2-column table with 5 rows. Column 1 is labeled Substance with entries upper Fe (S), Upper A l (s), Upper C u (s), Upper S n (s), Upper B p (s). Column 2 is labeled Specific heat capacity in joules per gram times degrees Celsius with entries 0,450, 0.897, 0.385, 0.227, 0.129.

Answer 1

Ranking (1 = fastest, 5 = slowest):

Pb: 1
Sn: 2
Cu: 3
Fe: 4
Al: 5

Reason: with equal mass and equal heating power, time ∝ specific heat capacity (less heat required → faster heating). For a 100 g sample warming ΔT = 60°C (e.g., 20 → 80°C), required heat Q = m c ΔT:

- Pb: 100·0.129·60 = 774 J
- Sn: 100·0.227·60 = 1,362 J
- Cu: 100·0.385·60 = 2,310 J
- Fe: 100·0.450·60 = 2,700 J
- Al: 100·0.897·60 = 5,382 J

(Assumes same initial temperature, identical heat transfer conditions, and same power from each hot plate.)