Achemist finds that when platinum is added to a reaction, the reaction speeds up. he thinks the platinum may be acting as a catalyst. what measurement should the chemist make to determine whether it is a catalyst?

measure the mass of the platinum before and after the reaction.
measure the temperature of the solution before and after the reaction.
measure the change in volume of the solution.
measure the amount of gas released by the reaction.

In a laboratory experiment, a fermenting aqueous solution of glucose and yeast produces carbon dioxide gas and ethanol. the solution was heated by burning natural gas in a bunsen burner to distill the ethanol that formed in the flask. during the distillation, the ethanol evaporated and then condensed in the receiving flask. the flame of the burner was kept too close to the bottom of the flask and some of the glucose decomposed into a black carbon deposit on the inside of the flask. during this experiment the following changes occurred. which of these changes involved a physical change and not a chemical change? check all that apply. 1-condensation of ethanol 2-evaporation of ethanol 3- formation of carbon dioxide gas from glucose burning of natural gas 4-formation of ethanol from glucose by yeast 5-formation of a carbon deposit inside the flask

Draw metallic bonding if two copper

Which of the following is most likely true about water in chemical solutions?