How much of one gram of radium-226 will remain unchanged after four half-lives?

Iron atoms have been detected in the sun's outer atmosphere, some with many of their electrons stripped away.

Which of the following correctly compares periodic properties of two elements and provides an accurate explanation for that difference? The first ionization energy of Al is greater than that of B because Al has a larger nuclear charge than B does.

An Mgion has the same electron configuration as? A) Ar B) Na° C) Ca2+ D) F-

How are atoms arranged in a network solid, such as a diamond? A) Covalent bonds join random sets of atoms into a loose, changeable structure. B) Intermolecular forces hold diatomic molecules in an array.

If you start with 5 molecules of o2 in the reaction how much mg will you need? a. 4 c. 8 b. 5 d. 10

What type of bond holds amino acids together?

If the ionization constant of water, kw, at 40°c is 2.92 * 10-14, then what is the hydronium ion concentration and ph for an acidic solution?

Do we get to see all sides of the moon? Why?

What does applied chemistry have to do with making ice cream?

If you visited a virtual Newton's Cradle website or played with the real device, you might have noticed that after a few swings, the balls slow down. The height they reach gets shorter and shorter until they finally stop moving.