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Assignment#1 1. Differentiate between primary and secondary raw materials for petrochemicals. Give example of each. 2. What are the acid gases in natural gas? Explain how they are removed. 3. Mass of 20 ml of petroleum based oil at 150C is 16.70 g. Calculate its API gravity. [Assume density of water @ 15C as0.998 g/ml). 4. What are the two methods used to liquefy natural gas? 5. Fill in the missing blanks in the following table. Structure Name Hydrocarbon type (Paraffin, Cycloparaffin, or Aromatic) H-CH C-H H-CK 1C-H U-I H H H 1 1 -C 1 1 H H H H H H 1 HCCH H-CH H H