two quick questions (1 Viewer)

[kooltrainer]

6) Explain how NaHCO3 is useful as a safety measure to minimise damage in chemical spills. Provide four points in support of your answer.

7)Write the formulae of the amphiprotic species in a solution of tetraprotic pyrophosphoric acid, H4P2O7.


i dun get what question 7 is asking. find the amphiprotic species in a solution of H4P2O7?

 

[Undermyskin]

7. Simply you need to write the ionization equations. Since it's a weak acid and also tertraprotic, there are four reactions like those for H3PO4 (only 3). You can write the equations on your own, here are the amphiprotic ions: H3P2O7-, H2P2O7 (2-), HP2O7 (3-)

6. NaHCO3 is super ideal (sorry, I'm a bit too fervent)

First, it's amphiprotic ---> handy for both acid and base neutralization

2nd, it's totally safe to handle and store because it's not corrosive or flammable or anything. and can be diposed of easily. (the tricky point is that you have to look at the chemical regulation authority of your local area)

3rd, when reacting, it releases CO2 which is harmless in low concentration and it reacts not vigorously like whizzzzzz or something, very gently.

Anything else? It's cheap...so?

 

[kooltrainer]

u no what r the equations to show HCO3- is amphiprotic?? i need help with that..

also.. dun quite understand what u mean in question 7

 

[yorkstanham]

As an acid: HCO<SUB>3</SUB><SUP>-</SUP> (aq) + H<SUB>2</SUB>O (l) « CO<SUB>3</SUB><SUP>2-</SUP> (aq) + H<SUB>3</SUB>O<SUP>+</SUP> (aq)

As a base: HCO<SUB>3</SUB><SUP>-</SUP> (aq) + H<SUB>3</SUB>O<SUP>+</SUP> (aq) « H<SUB>2</SUB>CO<SUB>3</SUB> (aq) + H<SUB>2</SUB>O (l)

 

[Undermyskin]

OK, I'll write all the equations:
Can you include the state yourself, plz?

H4P2O7 + H2O <--> H3P2O7- + H3O+

H3P2O7- + H2O <--> H2P2O7 2- + H3O+

H2P2O7 2- + H2O <--> HP2O7 3- + H3O+

HP2O7 3- + H2O <--> P2O7 4- + H3O+

Conclusion: H3..., H2..., H... are three amphiprotic substances! (this is sooo tedious)