ASAP When a cube of manganese oxide was added to a solution of hydrogen peroxide, water and oxygen were produced. Manganese oxide was not used up in the reaction. Which of the following is likely to increase the rate of the reaction?

A - Reducing the mass of the cube
B - Using a smaller amount of solution
C - Smashing the cube into pieces
D - Chilling the hydrogen peroxide solution

Americium-241 undergoes fission to produce three neutrons per fission event. if a neutron-absorbing material is mixed in with this sample so that the rate of neutron production drops down to 1.8 neutrons per fission event, which will be effective at achieving a critical mass? check all that apply. remove a deflective shield surrounding the sample. remove absorbent material mixed in with the sample. compress the sample of americium-241.