Which of the following is a characteristic of a mixture?
a. it has varying properties.
b. it has a fixed composition
c. it contains only pure substances
d. it has both varying properties and a fixed composition

Fill in the coefficients that will balance the following reaction: a0cr2(so4)3 + a1agno3

In the millikan oil drop experiment they determined that every drop had a charge which was a while number multiple of -1.60x10^-19. if a drop has a total charge of -9.60x10^-19 then how many excess electrons are contained within the drop?

Calculate the energy required to ionize a hydrogen atom to an excited state where the electron is initially in the n = 5 energy level. report your answer in kilojoules