Complete and balance these equation (if necessary):

(i) naoh(aq) + nh4cl(s) =

(ii) oh-(aq) + nh4+(aq) =

In this case, the NH4Cl is specified as a solid.

Its important to note that, as Im not convinced it can be written other than

Na+ (aq) + OH-(aq) NH4Cl(s) > NaCl(s) + NH3(g) + H2O(l)

which would serve as your ionic/net equation.

your molecular would be

NaOH(aq) + NH4Cl(s) ---> NaCl(s) + NH3(g) + H2O(l)

am curious what the higher ups have to say regarding this one! ;-)

astronomers such as edwin hubble.

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.