Compare the processes of distillation and reverse osmosis for desalination. What are the main differences in how each method works?

Distillation involves heating salty water to create steam, which is then condensed back into liquid, leaving salts behind. Reverse osmosis uses a semi-permeable membrane to separate water from salts by applying pressure to push water through the membrane.

A strong answer should directly address the approved learning objective to compare distillation and membrane processes such as reverse osmosis for desalination. This question belongs to Potable water within Using the Earth's resources and obtaining potable water, so the response should use that exact curriculum context rather than a generic statement. The answer is correct when it names the key idea, explains the link to desalination, and keeps the wording specific to AQA GCSE revision.