Ice melting is not a chemical change because .

A) a new reactant is formed
B) a new substance is not formed
C) a precipitate is no present
D) there is increased activation energy

Which statement is usually true about the relationship between activation energy and reaction rates? low activation energy barriers result in low rates. high activation energy barriers result in low rates. low activation energy barriers result in no reaction. high activation energy barriers result in no reaction.

How many grams of co(g) are there in 74.5 ml of the gas at 0.933 atm and 30o c?

Choose all the answers that apply. fluorine (f) has an atomic number of 9 and an atomic weight of 18.99. fluorine has a. 9 protons b. 10 neutrons c. 18 electrons d. an atomic mass of 19 e. at least one isotope