What occurs when the products have less enthalpy than the reactants?

A. Heat energy is absorbed

B. Heat energy is released

C. The reaction will be complete

D. The reaction will reverse

if a sample if pure sodium bas a mass of 8.2 grams and sodium has an average atomic mass of 22.99 g/mol, how many sodium atoms are there in the sample?

Which phrase best matches the definition of the term constellation? A. a group of stars that are nearby B. a group of stars that has a name C. a group of stars that are unknown D. a group of stars invisible to the naked eye

What is deoxyribonucleic acid, the name for DNA? It describes where DNA lives in the cell. It describes the structure of DNA. none of the above all of the above

When did the first particles of matter originate

How are antibodies and receptor molecules function similarly

How many grams of the excess reactant remain assuming the reaction goes to completion and that you start with 15.5g of na2s and 12.1g cuso4?

Which elements can be found in the sun? a. hydrogen and oxygen b. helium and oxygen c. hydrogen and helium d. hydrogen and nitrogen?

A sample of hydrogen gas at 2.0 atmospheres and 273 k occupies a volume of 5.0 liters. the gas sample is completely transferred to a 10.0-liter sealed, rigid container.

To make sure that the white powder was all sodium chloride and not mixed with sodium hydrogen carbonate, would you need to add a little less or a little more hydrochloric acid to the reaction?

A 10.0 gram sample of h2o at 23.0c absorbs 209 joules of heat. what is the final temperature