Which of these changes do not involve forming or breaking chemical bonds?

a.
burning and melting

b.
rusting and cutting

c.
burning and digesting

d.
boiling and melting

This is how zirconium appears in the periodic table. rounded to the nearest whole number, how many electrons are in an atom of zirconium?

The key to stability is feedback between the reservoir and the fluxes into and/or out of the reservoir. assume that the rate of outflow from a reservoir depends on the size of the reservoir according to the following relationship: outflow rate= k x (size of reservoir), where k is a constant. a reservoir of water has a volume of 5000 liters, and the rate of outflow at steady state is 25 liters per minute. what is k? (give both the numerical value and its units.) what is the residence time? what is the relationship between k and the residence time?

Debbie places two shopping carts in a cart corral she pushes the first cart which then pushes a second cart what force is being exerted