Which of the following describes the conversation of chemical energy to heat energy?

a: a chair sitting still

b: a leaf absorbing sunlight

c: a battery powering a cell phone

d: a rock hitting the ground

Miguel notices that on cold days his car's tire pressure light comes on but when the weather is hot the light is off. Explain why this happens using what you know about the gas laws.

does a reaction occur when an aqueous solution of calcium iodide and sodium sulfate are combined. If a reaction does occur write the net ionic equation.

What replaced the early pharmacists role in the production of medicine

O2 would not be considered as a compound. True False

What happens to the chemical identity of a substance during a physical change?

You sealed an Erlenmeyer flask that was determined to have a volume of 272.2 mL with a stopper. The density of air at 25°C is 0.001185 g/mL. Air has an effective molar mass of 28.96 g/mol. What amount of air was sealed in the flask?

Let's say we start with 2.2lbs of uranium. If the half-line of U-235 is 703.8 million years, how much uranium will we have after 2,815 million years

When sulfuric acid (h2so4) loses its hydrogen in exchange for calcium it becomes a (ch 8) : ?

A laboratory requires 2.0 L of a 1.5 M solution of hydrochloric acid (HCl), but the only available HCl is a 12.0 M stock solution. How could you prepare the solution needed for the lab experiment? show all work to find your answer

What is the primary function of neurons?