[" Which of the following is not a "],[" chemical reaction? "]

Which of the following can undergo a chemical reaction?

Which of the following can undergo a chemical reaction ?

Which of the following can undergo a chemical reaction?

Which of the following represents a chemical reaction ?

Which of the following represents a chemical reaction ?

A catalyst alters, which of the following in a chemical reaction?

Which of the following does not involve a chemical reaction?

Which of the following does not effect a chemical reaction in equlibrium? (Temperature, Pressure, Colour of reactants, Concentration)