Which of the following can be considered evidence of a chemical change? (Click the 4 that apply)

A. Evaportation

B. Production of a new substance

C. Production of Bubbles

D. Melting

E. Color change

F. Dissolving

G. Freezing

H. Heat is released

In what year was the first periodic table published

What is the smallest part gold can be broken into and still have all of gold's properties?

When molecules have a shorter bond length does it take more or less energy to break the chemical bond between those atoms?

A sample of liquid heptane (C7H16) weighing 11.50g is reacted with 1.300 moles of oxygen gas. The heptane is burned completely. After the reaction is complete, the amount of gas present is 1.050 moles. a. How many moles of CO are produced? b.

Which is not a reason why mass of an atom is expressed in atomic mass units rather than in grams?

An atom has an atomic number of 9 a mass number of 19 and an electron configuration of 2-6-1 explain why the number of electrons in the second and third shells shows that this is in an excited state

How can a chemical reaction be sped up? Pack in more of the reactant to increase the_.

How does a mixture of benzoic acid and benzaldehyde can be isolated separately by extractions?

What is a compound? a) a combination of two or more substances that are not chemically combined b) a combination of two or more elements that are combined in a certain ratio

A gas has a volume of 75mL at a pressure of 200.0 kPa. What will be the new volume be in mL if the pressure is decreased to 60.0 kPa in sig figs