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Physics

What is charge? How can it move through materials like metals? How does static electricity work? Is static electricity the same thing as ionisation because it is either losing or gaining electrons??
Hi,

Static electricity is caused when a non-conductive material known as a in insulator loses it's electrons from it atoms from the rubbing of 2 insulating materials. This gives the atoms an overall positive charge as there is more protons to electrons therefore yes, the atoms have been ionized. It can't move inside the insulator but if in contact with a conductive material such as a door handle the electricity is discharged and your atoms become neutral again.
Original post by Westsidegirl
What is charge? How can it move through materials like metals? How does static electricity work? Is static electricity the same thing as ionisation because it is either losing or gaining electrons??


Charge is a property of a particle that means it interacts with the electromagnetic force. When we talk about charge in terms of electricity, we are talking usually about a large group of electrons that are negatively charged.

Metals have a structure composed of positively charged metal ions and delocalised electrons. As they are delocalised, they can move freely throughout the metal which is what a current is.

Static electricity is when an object has an excess or defecit of electrons from when it is neutral so it is charged, positively or negatively. It's not quite the same thing as ionisation as ionisation is the process of removing electrons from induvidual atoms, but when an object is statically charged it has lost or gained electrons.
Original post by AHappyStudent
Charge is a property of a particle that means it interacts with the electromagnetic force. When we talk about charge in terms of electricity, we are talking usually about a large group of electrons that are negatively charged.

Metals have a structure composed of positively charged metal ions and delocalised electrons. As they are delocalised, they can move freely throughout the metal which is what a current is.

Static electricity is when an object has an excess or defecit of electrons from when it is neutral so it is charged, positively or negatively. It's not quite the same thing as ionisation as ionisation is the process of removing electrons from induvidual atoms, but when an object is statically charged it has lost or gained electrons.


Ahh okay thanks but where do the electrons come from in static electricity if it is not from the atoms itself?
Original post by Westsidegirl
Ahh okay thanks but where do the electrons come from in static electricity if it is not from the atoms itself?


When you rub two particular materials together, electrons from one will 'rub off' onto the other, transferring charge. If they're not metals then the atoms of one have been ionised.
Original post by Andrew Dawson
Hi,

Static electricity is caused when a non-conductive material known as a in insulator loses it's electrons from it atoms from the rubbing of 2 insulating materials. This gives the atoms an overall positive charge as there is more protons to electrons therefore yes, the atoms have been ionized. It can't move inside the insulator but if in contact with a conductive material such as a door handle the electricity is discharged and your atoms become neutral again.


thanks for replying, but I'm still confused because static electricity isn't dangerous like ionising radiation would be, and that causes electrons to be lost from the atom, so how can they be the same thing??
Original post by AHappyStudent
When you rub two particular materials together, electrons from one will 'rub off' onto the other, transferring charge. If they're not metals then the atoms of one have been ionised.


sorry for asking so many questions but if a metal loses electrons whats the difference?? Is that not ionisation as well??
(edited 6 years ago)
Original post by Westsidegirl
thanks for replying, but I'm still confused because static electricity isn't dangerous like ionising radiation would be, and that causes electrons to be lost from the atom, so how can they be the same thing??


Ionising radiation is dangerous to living organisms because it changes the structure of DNA, causing dangerous mutations in cells. Static electricity doesn't involve ionising DNA or anything so it's not dangerous in the same sense as radiation.

However, static electricity is still pretty dangerous. It can be a very large amount of charge stored in one place and I have heard of incidences where people have died when not being careful when using Van de graaf generators and stuff.
Original post by AHappyStudent
Ionising radiation is dangerous to living organisms because it changes the structure of DNA, causing dangerous mutations in cells. Static electricity doesn't involve ionising DNA or anything so it's not dangerous in the same sense as radiation.

However, static electricity is still pretty dangerous. It can be a very large amount of charge stored in one place and I have heard of incidences where people have died when not being careful when using Van de graaf generators and stuff.


You are really good at physics!! thanks so much :smile:
do you happen to be good at chemistry as well because i have my gcse exam soon and I am really confused?
Original post by Westsidegirl
sorry for asking so many questions but if a metal loses electrons whats the difference?? Is that not ionisation as well??


np. It's due to the difference in structure. Normal structures will involve ionisation as the electrons are still located in the orbitals of atoms. In metallic structures, there are already metal ions and delocalised electrons so removing these electrons isn't really ionising as the metal atoms have already been ionised.
Original post by Westsidegirl
You are really good at physics!! thanks so much :smile:
do you happen to be good at chemistry as well because i have my gcse exam soon and I am really confused?


I'm currently doing both physics at chemistry at AS so I know a fair amount about them, and I got A*s at both for GCSE. If you've got chemistry questions then I'd be happy to try to answer them but I'm not an expert
Original post by AHappyStudent
I'm currently doing both physics at chemistry at AS so I know a fair amount about them, and I got A*s at both for GCSE. If you've got chemistry questions then I'd be happy to try to answer them but I'm not an expert


Congratulations on your results! I can only dream to do that well

Incomplete combustion - is carbon produced as well as carbon monoxide?

Gortex (plastics) why is it breathable because you are layering PTFE over nylon which isn’t breathable.

In crude oil, are there alkenes present in it as well or is it just alkanes are alkenes only obtained from cracking??

What is photochemical smog and why does ozone cause breathing difficulties for humans because isn't it useful to reduce the UV rays coming from the sun?

(edited 6 years ago)
Thanks :smile:

Incomplete combustion - is carbon produced as well as carbon monoxide?


Both or either of them can be produced during incomplete combustion, and CO2 can be produced too. There's no single equation for it, either or both can be products. When writing an equation for incomplete combustion, make sure that you balance it though.

Also, a question may suggest that one may definately be produced. If the question mentions the production of black particulates then make sure that you include C in the equation.

Gortex (plastics) why is it breathable because you are layering PTFE over nylon which isn’t breathable.


I'm not sure but it's probably due to gaps in the structure that still allows transpiration to occur. Or, you're using such thin layers of PTFE and nylon that don't completely prevent the movement of small molecules such as H2O

In crude oil, are there alkenes present in it as well or is it just alkanes are alkenes only obtained from cracking??


No, both can be present in crude oil. During fractional distillation or other similar processes they will generally be seperated from one another as they have different boiling/melting points.

What is photochemical smog and why does ozone cause breathing difficulties for humans because isn't it useful to reduce the UV rays coming from the sun?


Photochemical smog is a mixture of gases, mostly nitrogen oxides and ozone that have been released by the decomposition of pollutants.

Ozone is pretty reactive so it can react with tissues which is pretty problematic. Haemoglobin (the chemical in your red blood cells that binds to O2) probably doesn't bond with O3 like it does with O2 (like CO), or respiration reactions cannot occur successfully with O3 instead of O2.
Original post by AHappyStudent
Thanks :smile:

Incomplete combustion - is carbon produced as well as carbon monoxide?



Both or either of them can be produced during incomplete combustion, and CO2 can be produced too. There's no single equation for it, either or both can be products. When writing an equation for incomplete combustion, make sure that you balance it though.

Also, a question may suggest that one may definately be produced. If the question mentions the production of black particulates then make sure that you include C in the equation.

Gortex (plastics) why is it breathable because you are layering PTFE over nylon which isn’t breathable.



I'm not sure but it's probably due to gaps in the structure that still allows transpiration to occur. Or, you're using such thin layers of PTFE and nylon that don't completely prevent the movement of small molecules such as H2O

In crude oil, are there alkenes present in it as well or is it just alkanes are alkenes only obtained from cracking??



No, both can be present in crude oil. During fractional distillation or other similar processes they will generally be seperated from one another as they have different boiling/melting points.

What is photochemical smog and why does ozone cause breathing difficulties for humans because isn't it useful to reduce the UV rays coming from the sun?



Photochemical smog is a mixture of gases, mostly nitrogen oxides and ozone that have been released by the decomposition of pollutants.

Ozone is pretty reactive so it can react with tissues which is pretty problematic. Haemoglobin (the chemical in your red blood cells that binds to O2) probably doesn't bond with O3 like it does with O2 (like CO), or respiration reactions cannot occur successfully with O3 instead of O2.



Literally a life saver! Thanks so much i won't bother you anymore with my questions but I am extremely grateful that you spent the time answering them
Original post by Westsidegirl
Literally a life saver! Thanks so much i won't bother you anymore with my questions but I am extremely grateful that you spent the time answering them


No problem, happy to help :smile:

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