Question
Coal, petroleum and natural gas cannot be prepared in the laboratory. Why?
✓
Answer
Coal, petroleum and natural gas cannot be prepared in the laboratory because: They are prepared at high temperature and pressure. They are formed from the remains of dead organisms. Their formation is a very slow process (take around $100$ million years to prepare). They are prepared in the absence of free oxygen (anaerobic). These all conditions are not available in the laboratory. Hence, coal, petroleum and natural gas cannot be prepared in the laboratory.
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