An element is a substance that cannot be broken down chemically into

A. electrons.

B. another substance.

C. atoms.

D. protons

Why do bromine vapors go up even thougj they are havier than air?

What happens to a stream when it is acidified?

What is the atomic number of xenon, the fifith element in group 18?

NaCl + H2O → NaOH + Cl2 + H2 How many grams of chlorine gas, Cl2 are given off if 7.5 grams of sodium chloride, NaCl, are decomposed? Is this equation balanced?

If an object has a mass of 3500 mg what is the mass in kg? Show detailed work

How did primo levi use his chemistry to survive Auschwitz?

Calculate the percent yield when 500 grams of carbon dioxide react with an excess of water to produce 640 grams of carbonic acid. CO2 + H2O - --> H2CO3

Which of the following is a possible equivalence that can be used in a conversion? A. ten to the negative second power hL over one L B. ten to the negative second power cL over one L C. ten to the first power L over one daL D.

Which process is a chemical change? burning a match boiling water melting ice breaking glass

What form of matter is "vapor"? a. a solid made of a substance that is usually liquid c. a gas made of a substance that is usually solid b. a liquid made of a substance that is usually gas d. a gas made of a substance that is usually liquid