What is the main idea behind the law of definite proportions?

For a particular reaction, the change in enthalpy is 51kJmole and the activation energy is 109kJmole. Which of the following could NOT be the change in enthalpy (ΔH) and the activation energy (Ea), respectively, for the catalyzed reaction?

If a hydrogen atom were to absorb a small amount of energy where would bohr say the electon would go?

A ball is dropped from a height of 20 meters. At what height does the ball have a velocity of 10 meters/second? A. 5.1 meters B. 9.8 meters C. 25 meters D. 15 meters

Write the nuclear equation for the release of the beta particles by Pb-210.

Sound and light energy travel from one place to another as waves. When this happens we say that the energy is: A) transpired B) transferred C) transported D) trans communicated which one is the correct one?

How could you compare the energy carried in two different longitudinal waves

The instantaneous velocity of an object is the blank of the object with a blank

Which of the following best describes the earth's average surface temperature for the past 900,000 years? A. a steady warming trend B. fairly steady temperatures until recently C. prolonged periods of cooling and warming D.

What should you always include in a great summary? (Select all that apply) A. investigation plan B. possible errors C. predictions D. new questions

What are the "base units" in the S. I. system?