02.3 Ethanol has a boiling point of 78.4^circ C and a melting point of -114.7^circ C Suggest why this method could not be used to separate a mixture of isopropanol and ethanol. [1 mark] __ 03 Models of the atom have changed over time. Exam Tip 03.1 Compare the plum pudding model of the atom to the earlier model. [3 marks] You'll need to m that are the sam that are differer 03.2 Explain how experimental evidence led scientists to suggest the nuclear model of the atom. [6 marks]

## Step1: For question 02.3, we need to understand why a specific method could not be used to separate a mixture of isopropanol and ethanol. The method in question is likely distillation, which relies on differences in boiling points. Ethanol has a boiling point of . Isopropanol has a boiling point of . The boiling points are very close, making it difficult to separate them effectively using simple distillation.## Step2: For question 03.1, we need to compare the plum pudding model to the earlier model of the atom. The plum pudding model, proposed by J.J. Thomson, suggested that the atom is a sphere of positive charge with negatively charged electrons embedded within it. The earlier model, proposed by John Dalton, described the atom as a solid, indivisible sphere without internal structure.## Step3: For question 03.2, we need to explain how experimental evidence led to the nuclear model of the atom. The key experiment was Rutherford's gold foil experiment. In this experiment, alpha particles were directed at a thin sheet of gold foil. Most particles passed through, but some were deflected at large angles. This suggested that the atom is mostly empty space with a small, dense, positively charged nucleus at the center. This led to the development of the nuclear model of the atom.#