How does reverse osmosis remove salt?
Many countries in dry regions rely on desalination, the process of removing salt from seawater, to supply their drinking water. In one common method, seawater is forced through very fine membranes that hold back the salt, a process known as reverse osmosis. The technology is effective, but it requires a large amount of energy, and the concentrated salty water left over must be released carefully so that it does not harm marine life. Engineers are therefore working on plants powered by solar energy and on membranes that need less pressure, hoping to make desalinated water cheaper and kinder to the environment.
Answer and explanation
Correct answer: A. By forcing seawater through fine membranes
- Step 1: The membranes hold back the salt.
Answer
By forcing seawater through fine membranes.
Why not the others: By boiling the water for hours, By adding chemicals that dissolve salt and By freezing the sea do not fit.
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