When the chemicals Methane (CH4) and Oxygen(O2) react, an explosion occurs. 1. Does the occurrence of the an explosion indicate a physical or chemical change?
2. Why does the explosion indicate this change?
3. What property is this?

When the water vapor cools it condenses select a number that represents his process on the

The human activities in two locations are described below: location a: rampant use of plastic containers location b: excessive use of pesticides and fertilizers which statement is most likely true? location a will have poor air quality because plastic is biodegradable. location a will experience water scarcity because plastic absorbs moisture. the population of honeybees will increase in location b because production of crops will increase. the population of fish in location b will decrease because the water is contaminated.

Water undergoes a large change in density at 0 ∘ c as it freezes to form ice. calculate the percent change in density that occurs when liquid water freezes to ice at 0 ∘ c given that