According to john dalton’s observations, when elements combine in a compound, a. the ratio of their masses is always the same. b. each element contributes an equal number of atoms. c. their volumes are always equal. d. their masses are always equal.

Match the following vocabulary terms to their definitions. 1. amount of energy required to change 1 gram of material from the solid to the liquid state at its melting point 2. a measure of the kinetic energy of the particles of a substance 3. the amount of heat energy required to raise the temperature of 1 gram of liquid water from 14.5°c to 15.5°c 4. amount of energy required to change 1 gram of material from the liquid to the gaseous state at its boiling point 5. the amount of energy required to change 1 gram of a substance 1°c a. temperature b. latent heat of vaporization c. latent heat of fusion d. calorie e. specific heat

Essay-alternative energy sources research sources of energy that are being developed. write a report of 350-400 words discussing the information you learned concerning the development of various energy sources and the impact that you think they will have on your life. include sources cited at the end of your report using the mla format. follow the rubric guidelines. note that wikipedia is not an appropriate resource for a research paper. worth 99

In a ball-and-stick molecular model, what do the sticks represent?