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hoochiscrazy

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danz90 said:
So then HDPE production is:

Low pressure, Low temp/High temp?

Organo-metallic and/or transition metal catalysts are used.

HDPE= Ziegler-Natta process
  • catalyst used-mixture of titanium (III) chloride and trialkylaluminium
  • temperature of about 60 degrees
  • Only few atmospheres of pressure=low pressure
 

JasonNg1025

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Describe some naturally occuring acids and their purpose in nature.

Citric acid (C6H8O7).
Errrrrr it makes fruit... taste nice?

If I got this question I'd go
Carbonic acid (H2CO3)
Carbonic acid acts as a buffer system in human blood. It uses the following equations:

H2CO3 <=> H+ + HCO3-
HCO3- <=> H+ + CO32-

When H+ is added, equilibrium shifts left, removing H+ ions and resisting pH change. When OH- is added, it reacts with the H+ forming <CODE>H2O</CODE>. This decrease in H+ causes equilibrium to shift right producing more.

Therefore, carbonic acid acts as a buffer for human blood, resisting pH change.
 

squeenie

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imqt said:
Guys aren't these two dot points the same?

DESCRIBE HOW TRANSURANIC ELEMENTS ARE PRODUCED

DESCRIBE HOW COMMERCIAL RADIOISOTOPES ARE MADE
(arnt transuranic elements be commercial radioisotopes?)
Transuranic elements are elements with numbers > 92.

Some commercial radioisotopes are Co-60 and Tn-99m.
 

JasonNg1025

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Guys aren't these two dot points the same?

DESCRIBE HOW TRANSURANIC ELEMENTS ARE PRODUCED

DESCRIBE HOW COMMERCIAL RADIOISOTOPES ARE MADE
Transuranic elements are elements with atomic number >92. Radioisotopes can be much smaller such as carbon-14. Their production methods are very similar, which may cause that confusion
 

Azreil

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imqt said:
Guys aren't these two dot points the same?

DESCRIBE HOW TRANSURANIC ELEMENTS ARE PRODUCED

DESCRIBE HOW COMMERCIAL RADIOISOTOPES ARE MADE
(arnt transuranic elements be commercial radioisotopes?)
Commercial radioisotopes need not be transuranic. For example, you may be able to argue Carbon-14 is a commericial radioisotope. Cobalt-60 certainly is and it's not transuranic.

It's the fission v fusion thing they're trying to get at I'm guessing.
 

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JasonNg1025 said:
Transuranic elements are elements with atomic number >92. Radioisotopes can be much smaller such as carbon-14. Their production methods are very similar, which may cause that confusion

thats why im getting confused
in nuclear reactors i have the production of AMERICUM as an example
in particle accelerators i have the production of CALIFORNIUM
but they are both transuranic elements


also btw which RECENT DISCOVERIES OF NEW ELEMENTS are yous using?
 

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imqt said:
also btw which RECENT DISCOVERIES OF NEW ELEMENTS are yous using?
Is "hoping it doesn't come up, sir!" a good answer to this question? =P

I vaguely know some stuff about Uup and Uuo.
 

JasonNg1025

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That's exactly why transuranic elements are produced in nuclear reactors and accelerators.

I am using

110 - Darmstadtium - Bombardment of lead with nickel - 1994

108 - Hassium - bombardment of lead with iron atom - 1984

EDIT: We all having lunch?
 
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imqt

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JasonNg1025 said:
That's exactly why transuranic elements are produced in nuclear reactors and accelerators.

I am using

110 - Darmstadtium - Bombardment of lead with nickel - 1994

108 - Hassium - bombardment of lead with iron atom - 1984

can you tell us about how much do you know of each? :uhoh: i hate this
 

JasonNg1025

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Well that's all I know.
Still hoping the exam won't have this.
How many should we know?
 

danz90

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imqt said:
can you tell us about how much do you know of each? :uhoh: i hate this
The one I did in detail was Darmstadium-269.
Darmstadtium-269 was produced in a heavy ion accelerator in Darmstadt, germany in 1994.

Nickel-62 ions were bombarded into Lead-208 ions, in a heavy ion accelerator, forming the nuclei of Darmstadium-269 and a neutron.

6228Ni + 20882Pb ---> 269110Ds + 10n
 

Azreil

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NEXT QUESTION! =D

Distinguish between strong and concentrated acids.
 

imqt

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danz90 said:
The one I did in detail was Darmstadium-269.
Darmstadtium-269 was produced in a heavy ion accelerator in Darmstadt, germany in 1994.

Nickel-62 ions were bombarded into Lead-208 ions, in a heavy ion accelerator, forming the nuclei of Darmstadium-269 and a neutron.

6228Ni + 20882Pb ---> 269110Ds + 10n

thankyou!
 

danz90

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Azreil said:
NEXT QUESTION! =D

Distinguish between strong and concentrated acids.
A strong acid is one that undergoes complete ionisation - ie. virtually all acid molecules present in the solution donate a proton to a base. Concentrated acids simply refers to the molarity, or amount of acid molecules present in solution per unit volume, and can be used to describe molarity of both weak and strong acids - ie. concentration acids have a high number of moles per unit volume of solution.

hope thats sufficient :uhoh:

imqt said:
thankyou!
no prob :)
hows ur study goin for 2moz
 

JasonNg1025

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Distinguish between strong and concentrated acids.
Strong acids are acids that fully dissosciate into ions in water. There is no molecular acid form present in water for strong acids. Concentrated acids are where there is a large number of moles of acid in an amount (1L) of water. Concentration can change for one particular acid, whereas strength cannot
 

JasonNg1025

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danz90 said:
hows ur study goin for 2moz
Terrible. Absolutely terrible...

EDIT: I'm off for lunch now. Hope it gets better when I come back :p
Just that I don't have much motivation... get bored and all that
 

danz90

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JasonNg1025 said:
Terrible. Absolutely terrible...
Same, as you can see im freaking procrastinating hard, right here...


*sings* "i haaate this part right heere..." :(
 

yorkstanham

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New Q:

Calculate the pH of the solution when 14ml of 0.1 mol/L sulfuric acid is mixed with 16ml of 0.12 sodium hydroxide
 

danz90

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yorkstanham said:
New Q:

Calculate the pH of the solution when 14ml of 0.1 mol/L sulfuric acid is mixed with 16ml of 0.12 sodium hydroxide
pH = 1.53 (2.s.f)
 

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