A 1.00 liter solution contains 0.45 M nitrous acid and 0.59 M sodium nitrite. If 0.150 moles of calcium hydroxide are added to this system, indicate whether the following statements are true or false. (Assume that the volume does not change upon the addition of calcium hydroxide.)
TrueFalse A. The number of moles of HNO2 will decrease. TrueFalse B. The number of moles of NO2- will remain the same. TrueFalse C. The equilibrium concentration of H3O+ will increase. TrueFalse D. The pH will increase. TrueFalse E. The ratio of [HNO2] / [NO2-] will increase.

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.