Which statement best characterizes chemical reactions?

They always occur very quickly.

Their rates vary significantly.

Their rates are always slow.

They rarely occur in the natural environment.

Iron reacts with oxygen in a chemical hand-warmer. How should this reaction be categorized? A. as an exothermic process because it releases heat B. as an endothermic process because it releases heat C.

Example of exothermic reaction:

What is true about the particles in a substance?

How many dL in 1,000 mL

What does the most accurate clock tell us

Why is a chemical indicator added to the flask in which a titration will occur? to show when enough base has been added to determine the starting pH of the solution to neutralize the acid before adding the base to identify the starting volume of

Mathematically define heat capacity

Based on what you read on the Marie Curie and the Science of Radioactivity website, name the scientists who shared the Nobel Prize in Physics in 1903 and describe their contributions that were recognized by the award.

What does aluminum hydroxide and calcium sulfate produce

Balnce the following molecular equation and write net ionic equation NaOH+H2SO4-Na2SO4+H2