I will give you a brainliest. Interpret the chemical equation in terms of numbers of moles of reactants and products.
2KCIO^3 (s) -> 2KCI (s) + 30^2 (g)

answer= 0.912 L or 912 mL

M(KClO3) =  122.55 g/mol

3.00 g KClO3 * 1  mol/122.55 g = 3.00/122.55 mol =0.02449 mol                

                          2KCIO3(s)=2KCI(s) + 3O2(g)

from reaction      2 mol                         3 mol

given                   0.02449 mol              x

x = 0.02449*3/2 =0.03673 mol O2

T = 24 + 273.15 = 297.15 K

PV = nRT

V= nRT/P = (0.03673 mol*0.082057 L*atm/K*mol*297.15 K)/0.982 atm =

= 0.912 L or 912 mL

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.