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TDS VS turbidity (1 Viewer)

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what is the difference between the two, don't they both measure the total amount of dissolved solids? Except for TDS you first filter to remove suspended solids.

also can someone explain the term suspended solids, and dissolved solids. I had a question which asked to calculate the turbidity. is the turbidity dissolved + suspended solids. or just the suspended solids?
 

HeroicPandas

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TDS = total dissolved solids = mass of solids that are dissolved in the water
Turbidity = in water, it means cloudness or LACK OF transparency as a result of suspended solids

DIFFERENCE: TDS does not include SUSPENDED SOLIDS, it only measures DISSOLVED SOLIDS
TURBIDITY is just a measure of cloudness in water which is as a result of SUSPENDED SOLIDS (maybe dissolved solids - like metal ions such as Fe2+ which causes solution to turn yellow-orange to pale yellow which can account for some degree of reduced transparency - this from my intuition)


Suspended solids are insoluble materials (eg. debris, or even mud)
Dissolved solids are solids that are dissolved in water forming a homogeneous solution

Turbidity is measure in NTU (nephlometric turbimetry units) which gives a measure of the amount of suspended solids present (so u just exclude dissolved solids when calcluating it)

"I had a question which asked to calculate the turbidity. is the turbidity dissolved + suspended solids. or just the suspended solids?" - just suspended solids
 
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someth1ng

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TDS = total dissolved solids = mass of solids that are dissolved in the water
Turbidity = in water, it means cloudness or LACK OF transparency as a result of suspended solids

DIFFERENCE: TDS does not include SUSPENDED SOLIDS, it only measures DISSOLVED SOLIDS
TURBIDITY is just a measure of cloudness in water which is as a result of SUSPENDED SOLIDS (maybe dissolved solids - like metal ions such as Fe2+ which causes solution to turn yellow-orange to pale yellow which can account for some degree of reduced transparency - this from my intuition)


Suspended solids are insoluble materials (eg. debris, or even mud)
Dissolved solids are solids that are dissolved in water forming a homogeneous solution

Turbidity is measure in NTU (nephlometric turbimetry units) which gives a measure of the amount of suspended solids present (so u just exclude dissolved solids when calcluating it)

"I had a question which asked to calculate the turbidity. is the turbidity dissolved + suspended solids. or just the suspended solids?" - just suspended solids
This part contradicted what you said previously. Dissolved solids can have an effect on the turbidity of water but typically, suspended solids are most responsible for it.

Total dissolved solids are things that are in solution. Suspended solids are not in solution.
 

HeroicPandas

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This part contradicted what you said previously. Dissolved solids can have an effect on the turbidity of water but typically, suspended solids are most responsible for it.

Total dissolved solids are things that are in solution. Suspended solids are not in solution.
1st point: i used a low modailty word "maybe" to expose my uncertainty
2nd point: why isnt suspended solids in a solution? this causes the cloudiness of some waters. Say i took a sample of highly turbid water, this solution would have to contain suspended solids
 
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hayabusaboston

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TDS = total dissolved solids = mass of solids that are dissolved in the water
Turbidity = in water, it means cloudness or LACK OF transparency as a result of suspended solids

DIFFERENCE: TDS does not include SUSPENDED SOLIDS, it only measures DISSOLVED SOLIDS
TURBIDITY is just a measure of cloudness in water which is as a result of SUSPENDED SOLIDS (maybe dissolved solids - like metal ions such as Fe2+ which causes solution to turn yellow-orange to pale yellow which can account for some degree of reduced transparency - this from my intuition)


Suspended solids are insoluble materials (eg. debris, or even mud)
Dissolved solids are solids that are dissolved in water forming a homogeneous solution

Turbidity is measure in NTU (nephlometric turbimetry units) which gives a measure of the amount of suspended solids present (so u just exclude dissolved solids when calcluating it)

"I had a question which asked to calculate the turbidity. is the turbidity dissolved + suspended solids. or just the suspended solids?" - just suspended solids

Nephelometric turbidity units**
 
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unfortunately, i can't find the actual question. but i did stumble onto something else. For determining the hardness of water quantitatively, why do they use mg of CaCO2/L as a measure of hardness. I though hardness was mass of calcium + magnesium/L??
 

someth1ng

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1st point: i used a low modailty word "maybe" to expose my uncertainty
2nd point: why isnt suspended solids in a solution? this causes the cloudiness of some waters. Say i took a sample of highly turbid water, this solution would have to contain suspended solids
If you can filter it out using filter paper, it is not in solution. Simple as that.
 

someth1ng

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Sunlight will stop photosynthesis but it will allow algae to continue respiring.

You want the biochemical oxygen demand which is the oxygen used by bacteria in water - you can only measure this is there's no oxygen constantly added to the water (ie stopping photosynthesis).
 

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