Help me with 23 fast

What type of electromagnetic radiation has a shorter wavelength than blue light

1) which of the following is the best example of a physical change? a) sugar dissolving in tea b) firefly glowing 2) in the combustion of ethane, what is/are the reactants? c2h6 + o2 ==> co2 + h2o a) c2h6 and o2 b) co2 and c2h6

How many moles of potassium hydroxide are needed to completely react with 2.94 moles of aluminum sulfate