Radium-221 has a half-life of 30 s. how long will it take for 95% of a sample to decay

If a substance is covalent, then it likely will

Electrochemistry is defined as a science that deals with the relation of electricity to chemical changes and the interconversion of chemical and electrical energy.

All matter is made up of atoms. Which sentence correctly describes atoms? a An atom is the smallest particle of an element. b Atoms are the smallest particle of a nucleus. c An atom is a substance that has been cut in half.

Which symbol represents an atom in the ground state with the most stable valence electron configuration? (1) B (3) Li (2) O (4) Ne

A motorcycle rider leans into the turns while going around the curves on a race track. Explain why the rider does this. A) The rider shifts their weight to keep their balance. B) The rider shifts their weight to create greater traction.

Carbonic acid (H2CO3) does not dissortate 100 percent in water. What type of substance is it? weak acid Strong base strong acid weak base

The standard enthapy of combustion of solid urea co (nh2) 2 is - 632kjmol-1 at 298k

What happens to an isotopes during radioactive

Why does the effective nuclear charge increase across a row of the periodic table?

Iodine-131 decays to form xenon-131. the half-life of this reaction is 8.07 days. from a 200-g sample of iodine-131, how much of the sample is xenon-131 after 16.14 days?