Given the unbalanced reaction: p₄+ o₂ p₄o₁₀ how many moles of o₂ are needed to produce 14.2 grams of p₄o₁₀­?
a. 0.125 mol
b. 0.0620 mol
c. 0.500 mol
d. 0.0500 mol
e. 0.250 mol

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

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How many moles is 14.5 cm^3 of platinum? the density of platinum is 21.45 g/cm^3.