When does a change in energy occur?

1. In some physical changes, but not all.

2. In every physical change, but not in a chemical change.

3. In every chemical or physical change.

2Nal + Cl2 → 2NACI + I2 How many grams of iodine are liberated if 546 g of chlorine react with excess sodium iodide? (I'm a really busy AP student with a lot of homework. Just need the work and answer!)

Convert 25 gram of carbon dioxide to mold

Which of the following is true? A) Gas atoms subjected to electricity emit bright lines of light. B) Gas atoms absorb white and emit a continuous spectrum of light. C) Gas atoms under high pressure emit dark lines against a continuous spectrum.

The reaction Ba (NO3) 2 (aq) + Na2SO4 (aq) → 2NaNO3 (aq) + BaSO4 (s) goes to completion because a

Consider the following reaction: AB (s) ⇌A (g) + B (g). At equilibrium, a 10.9 L container at 650 K contains A (g) at a pressure of 0.126 atm and B (g) at a pressure of 0.23 atm. The container is then compressed to half of its original volume.

What is the oxidation number for Our in NaHCO3?

To determine if a reaction is exoteric a student should use

Which of the following are physical properties of a penny? Choose all that are correct. Select one or more:a. Slightly red in color. b. Conducts electricity very well. c. Reacts to oxygen when heated. d. Resists corrosion from most acids.

NO2 and N2O4 undergo the reaction shown. When a sealed container of NO2 reaches chemical equilibrium, which must be true? A) No N2O4 is present. B) No chemical reactions are occurring. C) The rates of the forward and reverse reactions are equal.

What differences did you notice in the different states of water