Choose all the pairs of elements that will form a compound with an covalent/molecular bond a. phosphorus and iodine
b. rubidium and fluorine
c. sulfur and chlorine
d. aluminum and bromine

Identify the electromagnets with poles that are reversed from the electromagnet shown above

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.

Chemistry worksheet - i am not sure what they are asking for exactly?