1. A sample of radon has a half-life of 15 hours. What fraction of the sample is left

after

60 hours have passed?

The combustion of one gallon of automobile fuel produces About 5 pounds of carbon (in CO2). Two autos are making a trip of 600 miles. The first auto gets 20 miles per gallon, and the second gets 30 miles per gallon.

Which subatomic particles each have a negative electrical charge? A) protons B) neutrons C) electrons

What is the empirical formula of a compound that contains 32.39 percent sodium, 22.53 percent sulfur, and 45.07 percent oxygen?

At 200 degrees F, substance 1 is a liquid, substance 2 is a solid, and substance 3 is a gas. Which substance has molecules with no kinetic energy? A. Substance 1 B. Substance 2 C. Substance 3 D. None

Chloroform was used as an anesthetic for childbirth and surgery during the nineteenth century. Write the molecular formula of chloroform.

Give the four symbols for physical states of reactants and products, and tell what each means.

Which element is more electronegative, sulfur or nitrogen?

How does igneous rock become metamorphic rock?

The atomic mass oftitanium is 47.88 atomic mass units This atomic mass represents the 1) total mass of all the protons and neutrons in an atom of Ti 2) total mass of all the protons, neutrons, and electrons in an atom of Ti 3) weighted average mass

How many milliliters of. 45m hcl will neutralize 25ml of 1m koh?