A Helium Balloon contains 24.3 moles of Helium Gas. How many grams of Helium is this?

0.165 g

6.01 g

97.2 g

1.46 x 10^25 g

If 3.0 grams of strontium-90 in a rock sample remained in 1989, approximately how many grams of strontium-90 were present in the original rock sample in 1933?

Ph indicator strips work by changing color in the presence of solutions with varied ph values. thinking about your procedure steps and results in part 1, why do you think the ph of the unknown weak acid was not determined with ph indicator strips

In an effort to reduce the number of deaths due to Malaria, Scientist have successfully introduce a gene into mosquitoes. The gene makes the mosquito unable to support the development of the parasite that causes malaria.

How many moles of calcium are there in 5.74 x 1022 atoms of calcium?

If you have 100 grams of S8, how many moles of S8 is that

How can a chemical reaction be slowed down?

The atomic number of an element is always the same as ___ A. The number of electrons B. The number of protons C. The number of neutrons D. The number of protons plus neutrons

Covalent bonds are formed when electrons are

Complete the chart. (Remember to enter a "0" if necessary.) Atomic Number: 3 1s: 2s: 2p: 3s: 3p: 4s: 3d: 4p: 5s:

How many water molecules are in 2.25 mol of water?