If the initial amount of iridium-192 produces radiation at 1,000 times the safe level, how long will it take before radiation levels drop below the safe level?

Agas mixture with a total pressure of 745 mmhg contains each of the following gases at the indicated partial pressures: co2, 245 mmhg ; ar, 119 mmhg ; and o2, 163 mmhg . the mixture also contains helium gas. part a what is the partial pressure of the helium gas? phe p h e = nothing mmhg request answer part b what mass of helium gas is present in a 10.2-l sample of this mixture at 283 k ? m m = nothing g request answer

Pbco3 –> pbo+ co2. how many liters of carbon dioxide gas is produced from the decomposition of 32 grams of lead (ll) carbonate?

If a polyatomic ionic compound has gained two hydrogen ions, then how does its name begin?