Reactivity is not a physical property because it's a characteristic of a chemical element or compound and is involved in chemical process.
Hope u do well :) ik this maybe hard but you’ll get through it , the answer is D !
Actually, we can answer the problem even without the first statement. All we have to do is write the reaction for the production of sulfur trioxide.
2 S + 3 O₂ → 2 SO₃
The stoichiometric calculations is as follows:
7 g S * 1 mol/32.06 g S = 0.218 mol S
Moles O₂ needed = 0.218 mol S * 3 mol O₂/2 mol S = 0.3275 mol O₂
Since the molar mas of O₂ is 32 g/mol,
Mass of O₂ needed = 0.3275 mol O₂ * 32 g/mol = 10.48 g O₂
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Neutrons are responsible for combining with protons in the nucleus together to be held by the strong force. Too many neutrons in an atom will result in radioactive decay due to the neutrons' force overpowering the strong force.