chem p4

[intel1993]

Did silicon dioxide reacts with naoh........................
most of the books write its reaction with naoh...........bt in marksheme of j 2003 q3 its clearly indicate that sio2 does not react with Naoh..................


Wat u SAy??

 

[beacon_of_light]

what i know is that it doesn't react with NaOH ... yeah in some cases like hot(aq) NaOH the reaction is really very slow...

2 NaOH + SiO2 ----> Na2SiO3 + H2O

 

[intel1993]

ok thanks....bt i was confused that how most of the books can b ew rong at the same time......as many of them has written thes ame reactions as abv
bt thanx..............

 

[zeebujha]

what i know is that it doesn't react with NaOH ... yeah in some cases like hot(aq) NaOH the reaction is really very slow...

2 NaOH + SiO2 ----> Na2SiO3 + H2O

Yeps, we do require conditions of high concentration and temperature! Otherwise the bonds of SiO2 are too strong for the reaction too take place and thankfully so! Imagine aqueous NaOH in the lab reacting with the glass vessel in which it is containted! That would be great fun to watch!!!!!!!

 

[zain786]

Silicon dioxide also reacts with sodium hydroxide solution,
but only if it is hot and concentrated. Sodium silicate solution is formed.


check the question and if an equation is given then check the state symbols or description

 

[intel1993]

@zain : no eq given it only states deduct 1 mark if reaction written..........

 

[zain786]

WAT YR AND WHICH PAPER1 OR 2

 

[intel1993]

its paper 4

 

[zeebujha]

2003/ 20004 I think. The answer took me by surprise as well! Silicon Dioxide is acidic but reacts only under extreme conditions.

 

[zain786]

yea same here. ask ur teachr

it mite be a mistake on marking scheme