The half-life of u234 is 25200 years. how much of a 100 gram sample remains after 352800 years?

Which substances have the lowest melting points: ionic covalent, or metallic

Joe shines white light into a bowl half full of water at an angle of incident of 27.5°. calculate the angle of refraction in the water given the indices of refraction for air and water are 1.00 and 1.36, respectively.

Amixture that has two or more substances that are spread out evenly is called a. compound b. heterogeneous c. substance d. homogeneous