Answer:
(e) -6.1 J/K
Explanation:
Step 1: Given data
- Heat of fusion of ice (ΔH°fus): 333.5 J/g
Step 2: Calculate the heat (Qfreezing) required to freeze 5.0 g of water
We will use the following expression.
Qfreezing = -ΔH°fus × m
Qfreezing = -333.5 J/g × 5.0 g = -1.7 × 10³ J
Step 3: Calculate the entropy change (ΔS°) at 0 °C (273.15 K) and 1 atm
We will use the following expression.
ΔS° = Qfreezing/T
ΔS° = -1.7 × 10³ J/273.15 K = -6.1 J/K
The question is incomplete, the complete question is;
A magnet was placed near a pile that contained both iron and sulfur. The magnet was moved gradually closer to the pile. As it neared the pile, the magnet started attracting small pieces of iron from the pile. Which of these statements best describes the contents of the pile?
F. It is a homogeneous mixture of iron and sulfur. G. It is a heterogeneous mixture of iron and sulfur. H. It is a compound that contains both iron and sulfur. I. It is a compound that can be separated by magnetism.
Answer:
G. It is a heterogeneous mixture of iron and sulfur.
Explanation:
A heterogeneous mixture is one that does not have a uniform composition throughout.
We must recall that a mixture is any combination of substances that do not chemically react together and are separable by physical means.
Having said this, it is clear that I can separate the iron from sulphur by simple magnetic (physical) means. Hence, it is a heterogeneous mixture of iron and sulfur.
