Cho 2,8g hỗn hợp CuO, MgO, Fe2O3tác dụng vừa đủ với 50 ml dd H2SO41M. Cô cạn dung dịch sau phản ứng thu được m gam muối khan. Giá trị của m là:

plasma is the state of matter where the substance is ionized and has no definite shape or volume. the fact of being ionized makes the substance a good electrical conductor.

the ratio of the conjugate base to the acid required to attain the desired ph.

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.