If a substance changes color, what has most likely happened? A pressurized change has taken place.

A.) A chemical change has taken place.

B.) A physical change has taken place.

C.) Nothing has taken place.

Which of the following is not a definition of an acid? A substance that increases the hydroxide ion concentration of a solution A hydrogen ion donor in a reaction A substance that increases the hydronium ion concentration of a solution An

Approximately how many elements are there that combine chemically in a great number of ways to produce compounds? A. 25 B. 50 C. 75 D. 100

Write the balanced equation for the following equation: RbNO3 + BeF2-> Be (NO3) 2 + RbF

12. Describe the results of a chemical change. List four indicators of chemical change.

Energy of particles increase or decrease

Will an object with a density of 0.97 g/ml float or sink in water

Which subatomic particle contributes least to the mass of the atom? which subatomic particle contributes least to the mass of the atom? neutron electron proton all of these contribute equally?

2H2S (g) 2H2 (g) + S2 (g) Kc = 1.67 * 10 ^-7 at 800 C A 0.500 L reaction vessel initially contains 0.0125 mol of H2S at 800 C. Find the equilibrium concentrations of H2 and S2.

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_.