160 g of SO3 are needed to make 400 g of 49% H2SO4.
The equation of the reaction for the formation of H2SO4 from SO3 is given below as follows:
[tex]SO_{3} + H_{2}O \rightarrow H_{2}SO_{4}[/tex]
1 mole of SO3 produces 1 mole of H2SO4
Molar mass of SO3 = 80 g/mol
Molar mass of H2SO4 = 98 g/mol
80 g of SO3 are required to produce 98 og 100%H2SO4
mass of SO3 required to produce 400 g of 100 %H2SO4 = 80/98 × 400 = 326.5 g of SO3
Mass of SO3 required to produce 49% of 400 g H2SO4 = 326.5 × 49% = 160 g
Therefore, 160 g of SO3 are needed to make 400 g of 49% H2SO4.
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