A mass of 17.65 g for an unknown fuel was combusted in a reaction vessel containing an unknown amount of oxygen. At the end of the reaction, there still remained 17.59 g of the fuel as well as 0.0981 g of water and 0.1797 g of carbon dioxide. The oxygen was completely consumed during the reaction. How many molecules of oxygen gas were initially present in the reaction vessel?

Why does a red shoe appear red in daylight

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.

How many protons, electrons, and neutrons are in each of the following isotopes? a. zirconium-90 b. palladium-108 c. bromine-81 d. antimony-123