D: when sodium sulfide dissociates in water, the sulfur ion reacts with water as follows: s-2 + h2o → oh- + sh- which of the following statements is true? na2s is a base because it ionizes to release oh-. na2s is an acid because it is a proton donor. na2s is a base because it increases the hydroxide concentration. none of these

Option (a) is the correct answer.

Explanation:

A base is a substance that gives hydroxide ions () upon dissociation in water. This means that a base increases the hydroxide ion concentration in a solution.

On the other hand, an acid is a substance that gives hydrogen ions () upon dissociation in water. This means that an acid increases the hydrogen ion concentration in a solution.

For example,

Since, sodium sulfide () dissociates to give hydroxide ions.

Hence, we can conclude that is a base because it ionizes to release .

it should be p1 v1 = p2 v2

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.