Look at the diagrams below, showing mystery element A and mystery element D. How many valence electrons does mystery element A contain? Based on this, would it want to gain or lose electrons? Why is this? How many valence electrons does mystery element D have? Based on this, would it want to gain or lose electrons? Why is this?

the role of the microscope world in creating new materials .

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.