One situation indicates a physical change rather than a chemical change. which situation indicates a physical change?
a) solid copper melts to form liquid copper.
b) a firecracker explodes on the fourth of july.
c) water reacts with the iron on your bicycle to form rust.
d) magnesium metal is mixed with hydrochloric acid and hydrogen gas is formed.

Astone dropped into a well is heard to strike the water after 8seconds. find the depth of the well if the velocity of sound is 350m/s

The image shows the positions of a car on a roller coaster track. arrange the cars in order based on their gravitational potential energy. begin with the lowest potential energy and end with the highest.

Calculate the minimum energy required to remove one proton from the nucleus 126c. this is called the proton-removal energy. (hint: find the difference between the mass of a 126c nucleus and the mass of a proton plus the mass of the nucleus formed when a proton is removed from 126c.) express your answer with the appropriate units. emin e m i n = nothing nothing request answer part b how does the proton-removal energy for 126c compare to the binding energy per nucleon for 126c, calculated using eb=(zmh+nmn−azm)c2?