A. Dropping phenolphthalein test solution into colorless solution has no phenomenon, indicating that the solution is neutral, wrong, or possibly acidic, and phenolphthalein will not change color when it meets acid.
B, colorless gas burns in the air, producing gas that can make clear limewater turbid, indicating that the gas is methane, no, it may be carbon monoxide, ethane and other gases, because there are many gases generated by combustion.
C. After adding a few drops of detergent to the test tube containing a small amount of vegetable oil and water, the liquid oscillates and does not delaminate, indicating that the vegetable oil is soluble in water, which is wrong. This is because the vegetable oil is emulsified by the detergent and becomes very small droplets, but it is not soluble in water.
D, add about 1/3 of water to a soft plastic bottle filled with carbon dioxide, plug the cork, and vibrate, so that the plastic bottle becomes deflated, indicating that carbon dioxide can be dissolved in water. Correct, after carbon dioxide is dissolved in water, the air pressure in the bottle decreases, so it becomes deflated.
So choose d