[Borek]

To your first question of "How does a rocket move in space, where there is no air to push against?" the first law. It is pushing against it's own exhaust.

It is not the first law and it is not "pushing against" anything. That's very common misconception.

Rocket motion is better described as recoil. If you throw the stone, you will start moving in the direction opposite to where the stone was thrown. The only moment when there will be any forces present will be when you where throwing - one force was driving the stone, second one was directed opposite and it was driving you. That's the third law. It doesn't matter whether you throw a stone or - excuse le mot - fart, or use a rocket engine. It is exactly the same situation.

If throwing a stone doesn't set us in motion that's because we don't do that experiment in frictionless environement. Try it hanging in vacuum (thin air will do) and zero gravity (so that you don't stay on any stopping surface).

[Alpha-Omega]

When you all get tired of throwing around Newton's laws let me know....I have a better problem for you all to work on.....LOL this really turns some heads...

Can anyone provide me with the BALANCED redox RXN  for the combustion of sucrose used as a fuel for rocket fuel....commonly known as ROCKET CANDY...because I am just so blown by the fact that so many people feel this is a SPONTANEOUS RXN....

Sucrose + a nitrogen source....Yields..WHAT??   BALANCEED....can you help out

hOW ABOUT THIS ONE...

 KNO3(s) + CH2O(s) → 2 KNO2(s) + CO2(g) + H2O(g)

AND WHAT IS WRONG WITH THIS PICTURE....HOW IS THE RXN SUSTAINED.....EXACTLY...

OK is th rxn spontaneous or not?  What is the sustaining source....how eactly does it keep going....what is your source of oxygen....?  So many questions so few answers....


Anyone want to get into that argument...open to all responses...how does one overcome the activation energy required to drive the rxn to the left....and please feel free to give me a very basic answer that anyone can understand...

I so love this subject....Rocket Candy.....HOT TOPIC

[Borek]

Not one reaction, more like many concurrent processes taking place. When it comes to one balanced reaction I would go for something like

5C₁₂H₂₂O₁₁ + 48KNO₃ -> 24K₂CO₃ + 55H₂O + 36CO₂ + 24N₂

but don't treat it too seriously. In reality some CO will be produced, some soot as well, some mixture of nitrogen oxides, I wouldn't be surprised by traces of formaldehyde or formic acid.

[Alpha-Omega]

Glad to see your equation looks like me and Roberta's and Alexandra's....yes we have all 3 been doing work on this.....and yeah it of course is combustion and you get combustion products....Hard to convince people that lighting a match to start the reaction-means energy input is required to initiate the reaction..


It is how they think of "SPONTENEITY."

[Rabn]

Let's also keep in mind that magnitude of spontaneity (delta G) has no bearing on the kinetics of a reaction(except in very elementary reactions). A fine example is a diamond decomposing into graphite; spontaneous but very, very slow.