Ask me for chemistry help! (3 Viewers)

[MagnificentOne]

What is the difference between DO & BOD?

 

[kittyful]

What is the difference between DO & BOD?

DO - the level of required for high water quality for aquatic life to respire.
BOD - is the amount of DO required by organic matter

 

[Dylanamali]

What is the difference between DO & BOD?

DO = dissolved oxygen, it is the measurement of the amount of dissolved oxygen in a particular water sample. DO is good as a high level of dissolved oxygen is neccessary for cellular respiration which is essential for marine life etc.

BOD = biochemical oxygen demand - that is the amount oxygen utilised by organisms. A high BOD is not good, as it indicates the prescence of many microorganisms/bacteria.

 

[MagnificentOne]

Amphiprotic substances donate or accept H+ ions only, they are the simplest of them.
Amphoteric substances are defined as acids or bases on the lewis electron theory, that is, they donate lone electron pairs or accept lone electron pairs to make them basic/acidic.
So magnesium hydroxide can dissociate in water into hydroxide ions, making it basic, but magnesium can accept a lone pair from water, so it acts as a lewis acid

 

[MagnificentOne]

Define co-ordinate covalent bond.

 

[Dylanamali]

Amphiprotic substances donate or accept H+ ions only, they are the simplest of them.
Amphoteric substances are defined as acids or bases on the lewis electron theory, that is, they donate lone electron pairs or accept lone electron pairs to make them basic/acidic.
So magnesium hydroxide can dissociate in water into hydroxide ions, making it basic, but magnesium can accept a lone pair from water, so it acts as a lewis acid

hmm a bit complicated.. my definition was that amphiprotic can act as an acid or a base by accepting or donating H+ ions, according to Bronsted Lowry's theory whilst amphoteric substances were those that could just act as acids or bases (mainly included the oxides of semi metals)

 

[Dylanamali]

Define co-ordinate covalent bond.

A coordinate covalent bond is a bond in which both the shared electrons come from one atom. E.g. in ozone, carbon monoxide, ammonia etc.

 

[MagnificentOne]

What is the product of ammonia + hydrochloric acid ?

 

[kr73114]

DO - the level of required for high water quality for aquatic life to respire.
BOD - is the amount of DO required by organic matter

isnt BOD the amount of DO needed by aerobic bacteria to decompose organic matter fully?

 

[Dylanamali]

isnt BOD the amount of DO needed by aerobic bacteria to decompose organic matter fully?

yes, i think your right.

 

[kr73114]

What is the product of ammonia + hydrochloric acid ?

NH4+ and Cl-

 

[MagnificentOne]

NH4+ and Cl-

Its ammonium chloride

 

[kr73114]

Its ammonium chloride

lol

 

[Dylanamali]

MagnificentOne, you confident about tommorow's exam??

 

[kittyful]

Why is KCl an inappropriate solution to be used in a galvanic cell consisting of copper and silver ?

 

[Dylanamali]

Why is KCl an inappropriate solution to be used in a galvanic cell consisting of copper and silver ?

KCl as an electrolyte? which electrode is being put in the KCl?

 

[yew]

Because the chloride will react with the silver ions, forming a silver chloride precipitate. Which is undesirable. A more appropriate salt bridge to use would be KNO3

 

[kittyful]

yes KCL is the salt bridge solution

 

[Dylanamali]

yes KCL is the salt bridge solution

oh okay - then yes I agree with yew.

 

[yew]

Question: which of the following reagents would be most useful to separate barium ions from a solution which also contains magnesium ions?
a dilute h2so4
b potassium chloride solution
c sodium carbonate solution
d ammonia solution