<span>Among the given choices, the third option is the only one which illustrates single replacement.
(3)H2SO4 + Mg --> H2 + MgSO4
A single replacement is also termed as single-displacement reaction, a reaction by which an element in a compound, displaces another element.
It can be illustrated this way:
X + Y-Z → X-Z + Y</span>
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i think thats right
Answer : The partial pressure of 
and 
are, 84 torr and 778 torr respectively.
Explanation : Given,
Mass of = 15.0 g
Mass of = 22.6 g
Molar mass of = 197.4 g/mole
Molar mass of = 32 g/mole
First we have to calculate the moles of and .
and,
Now we have to calculate the mole fraction of and .
and,
Now we have to partial pressure of and .
According to the Raoult's law,
where,
= partial pressure of gas
= total pressure of gas
= mole fraction of gas
and,
Therefore, the partial pressure of and are, 84 torr and 778 torr respectively.
