The image above shows the movement of a wave over three seconds. what is the frequency of the wave?

a)2 hz
b)5 hz
c)1 hz
d)3 hz

The identities of substances are the same before and after which type of change

How much heat is added if 0.814g of water increase in temperature by 0.351 degree c?

How does a catalyst increase the speed of a reaction? a. the catalyst eliminates the activated complex stage, allowing products to form immediately. b. the catalyst lowers the energy level of the reactants, making it easier for them to react. c. the catalyst makes it easier for the activated complex to form, lowering the activation energy. d. the catalyst raises the energy level of the products, making the reaction finish sooner. reset next