You weigh a hydrate of CaCO3 with a mass of 40.8 g. After heating, the mass of the hydrate is 30.0 g. What is the formula for the hydrate?

Why are the trends and exceptions to the trends in ionization energy observed?

Joan writes four numbers on the board in standard form, and then she writes their scientific notation

Ageochemist examines a piece of metal that he found in the soil. he performs tests to identify the metal from its density, electrical conductivity, and melting point. which statement best describes his investigation? a. he is determining physical properties that are sufficient to identify the metal.b. he is determining chemical properties that are sufficient to identify the metal.c. he is determining physical properties that are insufficient to identify the metal.d. he is determining chemical properties that are insufficient to identify the metal.