Why is nahco3 a base?

(i need someone to explain it using the ka values)

h2co3 < --> hco3- + h+ ka = 4.3x10^-7
hco3- < --> co3^2- + h+ ka = 5.61x10^-11

if i underestand correctly, the kb for the second equation is greater than the ka. thus the reaction will not proceed forward, but rather produce more hco3-. this is a basic tendency. why is it more powerful than the first reaction?

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

24

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.