Will give brainliest!

What percentage of a substance remains after 7 half-lives have passed?

2.5

1.25

0.78

0.39

If the mass of 1 mole of chlorine atoms is 35.5g, calculate the mass of 6.0 moles of chlorine atoms.

5. If an atom has 12 electrons, how many energy levels are occupied

The mass of a single molybdenum atom is 1.59*10-22 grams. How many molybdenum atoms would there be in 40.6 milligrams of molybdenum?

Many of the items you purchase are mixtures of pure compounds. Select three of these commercial products and prepare a list of the ingredients that are pure compounds.

21. Draw Lewis structure Lewis structures for each of the followi olecules. (Hint: See Sample Problem D.). a contains one C and four F atoms b. contains two H and one Se atom c. contains one N and three I atoms d.

Great white sharks live in the waters around California and feed on seals. Changes in his ecosystem have caused the seal population to decrease. Which result is an adaptation by sharks when there are fewer seals to eat? A.

Which of the following changes occurs with the greatest increase in entropy?

A child sits on a partially filled balloon and decreases the volume by half. What happens to the pressure inside of the balloon?

Which phrases describe all the outer planets' motion? Check all that apply. no rotation fast rotation slow revolution opposite revolution north to south rotation

Rank the species (amide ion, ammonia, or ammonium ion) from the largest to the smallest H-N-HH-N-H bond angle? Rank from largest to smallest H-N-HH-N-H bond angle. To rank items as equivalent, overlap them.