Unit 4 Questions MEGATHREAD!

[Asx4Life]

Does temperature increase the rate of movement of particles when talking about rate of reaction? Or does it only give reactant particles more energy to overcome the activation energy barrier?

I want to know this too. Does increasing temperature increase the speed at which particles collide meaning more particles will hit with a higher energy hence raising the rate of reaction or raising the temperature just increases the number of the number of collisions, or both?

[Graphite]

Both

[Mao]

True that but I was just point out that such a thing happens in nature

But such a thing does not happen in nature. Maybe you are talking about evaporation?

[Graphite]

True that but I was just point out that such a thing happens in nature

But such a thing does not happen in nature. Maybe you are talking about evaporation?

What do you mean it doesn't happen? You said yourself its negligible but that doesn't mean it doesn't occur

[Mao]

True that but I was just point out that such a thing happens in nature

But such a thing does not happen in nature. Maybe you are talking about evaporation?

What do you mean it doesn't happen? You said yourself its negligible but that doesn't mean it doesn't occur

Righto. If we combust 1 mol of methane (16 g), we will see a mass loss of 10 picograms. Or one part per trillion.

You find me an instrument that can measure this kind of mass difference, or you find me a case when this one part per trillion loss makes any meaningful difference, and I'll agree with you. My point is that you don't have a valid point.

[Asx4Life]

Both

Is this the same case for concentration and pressure?

[Graphite]

Both

Is this the same case for concentration and pressure?

No, concentration and pressure cannot supply energy to the molecules

[Graphite]

True that but I was just point out that such a thing happens in nature

But such a thing does not happen in nature. Maybe you are talking about evaporation?

What do you mean it doesn't happen? You said yourself its negligible but that doesn't mean it doesn't occur

Righto. If we combust 1 mol of methane (16 g), we will see a mass loss of 10 picograms. Or one part per trillion.

You find me an instrument that can measure this kind of mass difference, or you find me a case when this one part per trillion loss makes any meaningful difference, and I'll agree with you.

I don't understand what we are arguing here. I am saying this small mass although is small, it is lost nonetheless. I am not trying to say its significant. Whether it occurs or not and whether its significant is a different matter, right?

[Christiano]

It says in A+ notes that temperature only increases the energy levels of the particles, not the frequency of collisions. I'm confused now.

[Asx4Life]

It says in A+ notes that temperature only increases the energy levels of the particles, not the frequency of collisions. I'm confused now.

Maybe increasing the kinetic energy of particles wont necessarily increase the number of collisions because faster particles mean they can also dodge each other as easily as it will collide. So there will be no difference... Okay, I think I'm just talking nonsense. Can anyone clarify please?

[HarveyD]

the effect of the increased velocity of the particles is insignificant in comparison to the effect of the increased average kinetic energy in terms of reaction rate, hence thats probably why they left it out

i think...

[Mao]

the effect of the increased velocity of the particles is insignificant in comparison to the effect of the increased average kinetic energy in terms of reaction rate, hence thats probably why they left it out

i think...

The average kinetic energy is very related to the average velocity. Both are significant.

[Mao]

I don't understand what we are arguing here. I am saying this small mass although is small, it is lost nonetheless. I am not trying to say its significant. Whether it occurs or not and whether its significant is a different matter, right?

No. The point I'm making is doesn't matter if this effect exist or not, it will not make any difference. It'll be similar to me pointing out in the collision theory, all molecules experience tiny amounts of relativistic effects. It is completely useless in the field of chemistry. We don't even care if it occurs or not, because it won't make a difference.

[Graphite]

OK Professor Mao

[b^3]

When a Fe²⁺/Fe half-cell is connected to a Sn²⁺/Sn half-cell, the tin electrode is positive. However, the tin electrode is negative when the Sn²⁺/Sn half-cell is connected to a Fe²⁺/Fe half-cell.
a) Explain this fact.
b) Which of Fe²⁺, Fe³⁺, Sn²⁺ or Fe is the best oxidant in this systen?

Is it just me or does the information given just go around in a circle?
Apon typing this I think the question may have a small mistake, should one of the Fe²⁺/Fe half-cells have a Fe³⁺ instead of a Fe?