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Question Chain Thread !!! (2 Viewers)

eddy11

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yorkstanham said:
What properties of technetium-99m make it more suitable for medical imaging that cobalt-60?
technecium-99m is easily incorporated into a range of biological molecules. This means that it can be incorporated into molecules that are accumulated by specific by organs in the body. Thus, specific organs are able to be imaged . Cobalt-60 is not taken up by organs in the body, thus it cannot be use to produce detailed images that can reveal whether an organs physiology is correct, or the subtleties in the shape and structure which may be indicative of abnormal growth of an organ that may be shown by Tc-99m

Edit: i wish i hadnt posted after danz90

Describe recent discoveries of elements
 
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axlenatore

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JasonNg1025 said:
I dunno... just try and remember the "1" ones... generally the +- 1s in the periodic table are soluble.

I like to imagine very ridiculous things to remember it, cause they somehow stick in my head.

So once I see a metal from group one I immediately think of stuff dissolving. I don't know why, but once I see an alkali ion my brain just switches to "dissolve, dissolve, dissolve"

From there, I think "wait, anything similar should also dissolve and hence ammonium salts should dissolve"

Then I think "if that works then other 1s should also dissolve, such as the halogens, NO3 and CH3COO"

Sulfates are soluble cause they both start with S :p. But sulfides aren't because the sulfide group is purely sulfur, sulfur does not dissolve.

Think of silver, lead and mercury as antagonists... they make dissolving impossible for halogens and sulfates.

I don't know how to remember hydroxides and oxides, they're insoluble, if you keep worrying about it it may just stick in :p

Exceptions -

Barium and calcium - they love reversing things. Reversed from above rules for sulfates, hydroxides, oxides. Remember your chain of thought: you think of group 1 first, group 1 gets priority. All group 1s and ammonium salts are exceptions to the "insoluble" groups.

Took my ages to write, sorry
You need to only know the soubility rules for the ones specified in the syllabus, but knowing things like all nitrates and sodium thingys are soluble.
 

danz90

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JasonNg1025 said:
I dunno... just try and remember the "1" ones... generally the +- 1s in the periodic table are soluble.

I like to imagine very ridiculous things to remember it, cause they somehow stick in my head.

So once I see a metal from group one I immediately think of stuff dissolving. I don't know why, but once I see an alkali ion my brain just switches to "dissolve, dissolve, dissolve"

From there, I think "wait, anything similar should also dissolve and hence ammonium salts should dissolve"

Then I think "if that works then other 1s should also dissolve, such as the halogens, NO3 and CH3COO"

Sulfates are soluble cause they both start with S :p. But sulfides aren't because the sulfide group is purely sulfur, sulfur does not dissolve.

Think of silver, lead and mercury as antagonists... they make dissolving impossible for halogens and sulfates.

I don't know how to remember hydroxides and oxides, they're insoluble, if you keep worrying about it it may just stick in :p

Exceptions -

Barium and calcium - they love reversing things. Reversed from above rules for sulfates, hydroxides, oxides. Remember your chain of thought: you think of group 1 first, group 1 gets priority. All group 1s and ammonium salts are exceptions to the "insoluble" groups.

Took my ages to write, sorry
Cheers :)

Well, I guess I know general ones, but if they give me something really out of the blue, I'll just take a punt lol

Although, most phosphates and carbonates are insoluble (except the first group elements). I generally have a rough idea of which common ones are insoluble and soluble.
Test me with a few lol
 

JasonNg1025

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yorkstanham said:
just answer the question!
Where did you get this question? Usually Co-60 is more suitable because it's got a lower half life of around 5 years compared to technetium-99 which has a half life of a couple of hundred thousand years.
 
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axlenatore

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JasonNg1025 said:
Where did you get this question? Usually Co-60 is more suitable because it's got a lower half life of around 5 years compared to technetium-99 which has a half life of a couple of hundred thousand years.
Nope.

Cobalt-60 which is a strong gamma emitter is used in the irradiation of food materials. The food moves along a conveyer belt through a chamber containing the cobalt-60 which emits gamma rays onto the food which effectively destroys any harmful microbes housed in the food thus making it safer to eat whilst persevering it for a longer period of time. The advantages of using cobalt-60 is that it has a long half life of 5.3 years so it doesn’t need to be replaced regularly and doesn’t emit enough gamma radiation to make the food harmful, but as a disadvantage may destroy some of the nutrients in the food and also workers need to be protects thus making the use of this more expensive and possible dangerous
Technetium-99m is a gamma emitter which a half life of six hours which means to patients exposure is minimised. The gamma radiation emitted from the nucleus which is easily picked up by imaging machinery allowing it to detect any abnormalities in its movement around the body <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" /><o:p></o:p>
 

JasonNg1025

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danz90 said:
Cheers :)

Well, I guess I know general ones, but if they give me something really out of the blue, I'll just take a punt lol

Although, most phosphates and carbonates are insoluble (except the first group elements). I generally have a rough idea of which common ones are insoluble and soluble.
Test me with a few lol
Sodium Phosphate, gogogo
 

JasonNg1025

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axlenatore said:
Nope.

Cobalt-60 which is a strong gamma emitter is used in the irradiation of food materials. The food moves along a conveyer belt through a chamber containing the cobalt-60 which emits gamma rays onto the food which effectively destroys any harmful microbes housed in the food thus making it safer to eat whilst persevering it for a longer period of time. The advantages of using cobalt-60 is that it has a long half life of 5.3 years so it doesn’t need to be replaced regularly and doesn’t emit enough gamma radiation to make the food harmful, but as a disadvantage may destroy some of the nutrients in the food and also workers need to be protects thus making the use of this more expensive and possible dangerous
Technetium-99m is a gamma emitter which a half life of six hours which means to patients exposure is minimised. The gamma radiation emitted from the nucleus which is easily picked up by imaging machinery allowing it to detect any abnormalities in its movement around the body ffice:eek:ffice" /><o>:p></o>:p>
Is this medical or food imaging....

Thanks danz... I get it now :D
 

axlenatore

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JasonNg1025 said:
Is this medical or food imaging....

Thanks danz... I get it now :D
I was just showing you how the half life you stated before were quite off
 

JasonNg1025

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axlenatore said:
I was just showing you how the half life you stated before were quite off
Ohhh ok
Sorry mate
I must be thinking about another radioisotope
I guess you're right then :D
 

danz90

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JasonNg1025 said:
Insoluble, cause lead is a meanie

Calcium sulfate
Mostly insoluble, however quite soluble in excess hot water.

Lead Sulfate
 

axlenatore

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danz90 said:
Soluble, since all Na+ is soluble :)

Ummm..
Lead Chloride
goo
debatable, depends on the molarity, texts books say its insoluble but practically through experiements due to the low molarity of solutions used in school we havent been able to get a precipitate, which was off putting in the prac test..
 

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danz90 said:
Mostly insoluble, however quite soluble in excess hot water.

Lead Sulfate
And you were saying you didn't know.

Insoluble? Cause I think lead was also a meanie to sulfate
 

JasonNg1025

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axlenatore said:
debatable, depends on the molarity, texts books say its insoluble but practically through experiements due to the low molarity of solutions used in school we havent been able to get a precipitate, which was off putting in the prac test..
Would it have been too tiny you couldn't see if it was small amounts?
 

danz90

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JasonNg1025 said:
And you were saying you didn't know.

Insoluble? Cause I think lead was also a meanie to sulfate
Well, like I said, I know the more common ones. If they throw some weirdo one, I might not know.

Correct, its insoluble. ;)

Barium Hydroxide
 

axlenatore

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JasonNg1025 said:
Would it have been too tiny you couldn't see if it was small amounts?
Well we werent able to notice the precipitate the solution just remained clear instead of going milky white
 

axlenatore

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danz90 said:
Well, like I said, I know the more common ones. If they throw some weirdo one, I might not know.
Uranium phosphate
 

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