C12H22011+1202-->12CO2+11H20
if 49.8 L of O2 are consumed, how many moles of sucrose are required?

0.185moles

Explanation:

Given parameters:

Volume of O₂  = 49.8L

Unknown:

Number of moles of sucrose required  = ?

Solution:

We can assume that the reaction takes place at standard temperature and pressure.

From this, we can find the number of moles of oxygen that reacted and extrapolate to that of sucrose.

Chemical equation;

           C₁₂H₂₂0₁₁  +  120₂   →   12CO₂   +   11H₂0

Number moles  =   at STP

Number of moles of oxygen gas =   = 2.22moles

           12 moles of oxygen gas combines with  1 mole of sucrose

       2.22 moles of oxygen gas will combine with   = 0.185moles

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.