Use the unit-factor method (aka dimensional analysis). Set the calculation up to cancel out the units you don't want and leave the units you do.
2C2H2(g) + 5O2(g) --> 4CO2(g) + 2H2O(g)
???g ........................ .. 275.4 kg
275.4 kg CO2 x (1000g / 1 kg) x (1 mol CO2 / 44.0g CO2) x (1 mol C2H2 / 2 mol CO2) x (26.0g C2H2 / 1 mol C2H2) = 81,370g C2H2 ... or ... 8.137x10^4g C2H2 ............ The answer is rounded to four significant digits
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Mass of C2H2 (acetylene).....
Use the unit-factor method (aka dimensional analysis). Set the calculation up to cancel out the units you don't want and leave the units you do.
2C2H2(g) + 5O2(g) --> 4CO2(g) + 2H2O(g)
???g ........................ .. 275.4 kg
275.4 kg CO2 x (1000g / 1 kg) x (1 mol CO2 / 44.0g CO2) x (1 mol C2H2 / 2 mol CO2) x (26.0g C2H2 / 1 mol C2H2) = 81,370g C2H2 ... or ... 8.137x10^4g C2H2 ............ The answer is rounded to four significant digits