The pile of ash left after a fire burns out demonstrates what concept? A. Original materials remain after a physical change. B. A chemical change forms new substances. C. Physical properties are never stable. D. Fire recycles most substances.

What is the frequency of a 670 nm light wave? 4.5 x 106 s-1 2.2 x 106 s-1 2.2 x 1014 s-1 4.5 x 1014 s-1

An aqueous solution at 27°c contains 3.6 g of a protein in a 200 ml sample. the osmotic pressure is 0.0203 atm. what is the molar mass of the protein

Which compound is sometimes found in fire extinguishers

Whitch is a type of mining where steam beds are minded

Explain how the climate in a specific region differs during El Niño and La Niña I know this isn't chemistry but I couldn't find Science!

How many grams of sodium ions are in na2so4?

Electron configuration for iron?

Explain how melting is considered endothermic

In the process of covalent bonding, atoms share electrons. This means that * a) Electrons from each atom are attracted to the nucleus of both atoms b) Protons and neutrons attract c) Atoms lose electrons and become ions d) Atoms gain electrons and

Give the full atomic symbol for an atom that has 30 neutrons and an atomic number of 25