Which of the following is an example of how a scientist might use a model? a) a stopwatch is used to time the rate of a chemical reaction b) the end of a slinky is moved vertically up and down to simulate a wave c) a microscope is used to magnify a group of cells on a slide d) a wrench is used to tighten a nut onto a piece of wood p. s.- this is science not chemistry

If a || b and e || f, what is the value of y ?

The atomic radius of sodium is 186 pm and of chlorine is 100 pm. the ionic radius for na+ is 102 pm and for cl– is 181 pm. in going from na to cl in period 3, why does the atomic radius decrease while the ionic radius increases? a. the inner electrons in the sodium cation shield its valence electrons more effectively than the inner electrons in the chloride anion do. b. the inner electrons shield the valence electrons more effectively in the chlorine atom than in the chloride anion. c. the outermost electrons in chloride experience a smaller effective nuclear charge than those in the sodium cation do. d. the outermost electrons in chloride experience a larger effective nuclear charge than those in the sodium cation do. e. monatomic ions are bigger than the atoms from which they are formed.

The image shows a process that releases nuclear energy which statement best identifies the process shown the process must be fusion because energy is released the process must be fusion because of have your nucleus formed a smaller nuclei the process must be fission because a large nucleus breaks into smaller nuclei the process must be fission because neutrons are formed