Which type of matter can be separated only by physical change

Select the correct answer. Why does every chemical reaction require a certain amount of activation energy? O A Energy is released when the reactants begin to react. O B. Energy lost to the environment during the reaction must be replaced.

Explain how might a renewable energy source become nonrenewable

What volume will a sample of hydrogen occupy at 28.0 oc if the gas occupies a volume of 2.23 ml at a temperature of 0.0 oc? assume that the pressure remains constant. (remember to change to kelvin) ?

Dose force of attraction between the gas particle are weaker than between the liquid particles?

Write the electrons configuration for an atom of an element whose atomic number is 8

Which combination of protons neutrons and electrons is correct for the isotope of copper - 63?

What is the purpose of a domain?

What is the ideal gas constant? A. It is a constant that applies only at STP. B. It is a specific constant for a particular gas. C. It is a universal constant used for all gases. D. It is a constant that depends on the conditions.

The greenhouse effect is a result of the Sun's energy being absorbed by objects on the Earth and converted into which type of radiation? A) Radio B) Visible C) Infrared D) Ultraviolet

Which was the limiting reactant: the zinc or the hydrochloric acid? Remember that the limiting reactant is completely consumed in a reaction and no new product is formed unless more of the limiting reactant is added.