Use the ideal gas law PV = nRT and manipulate it to solve for n. PV/RT = n.
Convert to SI units:
660ml -> 0.660 L
27 degrees -> 300 K
Leave Pressure as is
Use 62.36368 for R becuase you are using mmHg for Pressure.
Now plug into the equation to get about 0.025928 mols. Divide the 3.30 grams by the mols to get about 127 g/mol.
Multiply the weight of the object by the distance it traveled to find the amount of work output. For the example: 10 lbs. x 1 foot = 10 foot-pounds. Find the work efficiency by dividing the work output by the work input and multiplying by 100.
100.0 g KClO₃ × 1 mol KClO₃/122.55 g KClO₃ × 2 mols KCl/2 mols KClO₃= 0.8160 mols of KCl
100.0 g KClO₃ × 1 mol KClO₃/122.55 g KClO₃ × 3 mols O₂/ 2 mols KClO₃= 1.224 mols of O₂
try this
122.55 g is molar mass of potassium chlorate
Answer:

Explanation:
Hello there!
In this case, according to the given chemical reaction, it is possible to realize there is a 1:2 mole ratio of sulfuric acid to water; thus, given the mass of the former and its molar mass (98.07 g/mol), it is possible to determine the mass of produced water as shown below:

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