Which of these energy resources does not pollute when used?
oa) coal
ob) petroleum
o natural gas
od) hydroelectric

You 4. you have been swimming in your neighbor’s pool for an hour. the relative humidity of the air is 30 percent. will you feel warm or cool when you step out of the pool? explain your answer.

Drag each label to the correct location on the chart. classify each reaction as endothermic or exothermic.

An atom of sodium-23 (atomic number = 11) has a positive charge of +1. give this information, how many electrons does it have? how many proteins and neutrons does this atom have