What does every chemical reaction involve?

A change in state.

A change in mass.

A change in energy.

A change in concentration.

The comparison of the number of atoms in a copper coin the size of a penny with the number of people on earth is made to illustrate which of the following? a. that atoms are indivisible b. that atoms are very small c. that atoms are very large d. that in a copper penny, there is one atom for every person on earth

What energy conversion occurs when a sling shot is used to shoot a rock across the room? (2 points) question 2 options: 1) stored mechanical energy is converted to mechanical energy. 2) stored mechanical energy is converted to radiant energy. 3) gravitational energy is converted to radiant energy. 4) gravitational energy is converted to mechanical energy.

An unsaturated hydrocarbon is a hydrogen-carbon compound with a. a network solid structure b. single bonds c. single bonds in a branched-chain structure d. double or triple bonds