Which of these is an example of a physical change

baking a cake

toasting bread

grinding pepper

lighting up a grill

Which of the following energy level changes for an electron is most energetic? 3 → 2 5 → 2 4 → 2

If one object has a positive charge and another has a negative charge, the object will what? Cancel Attract Mix Repel

All parts of the nervous system except of the brain and spinal cord makes up the a. Central nervous system b. Peripheral nervous system c. muscular system d. Nerve

If 25.0 g of NH3 and 38.9g of O2 react in the following reaction, how many grams of NO will be formed? 4 NH3 (g) + 5 O2 (g) → 4 NO (g) + 6 H20 (g)

18 g of argon occupy 750 ml at a particular temperature and pressure. How many grams of methane would occupy the same volume at the same temperature and pressure?

How should scientist respond when new evidence that challenges current is presented?

Consider the following reaction, equilibrium concentrations, and equilibrium constant at a particular temperature. Determine the equilibrium pressure of H2. D2 (g) + H2 (g) ⇌ 2 HD (g) Kp = 1.80 P (D2) eq = 1.1 * 10-3 atm P (HD) eq = 2.7 * 10-3 atm

Find δe for the change in state of 1.0 molh2o (l) at 79 ∘c to h2o (g) at 116 ∘c. the heat capacity of h2o (l) = 75.3 j/molk, heat capacity of h2o (g) = 25.0 j/molk, and the heat of vaporization of h2o is 40.7*103j/mol at 100 ∘c.

Balloon A started with a volume of 1.76 L. The temperature of the room the balloon was in was 295 K. The balloon was heated to a temperature of 253.15 K. What is the new volume?

The standard internal energy change for a reaction can be symbolized as ΔU°rxn or ΔE°rxn. For the following reaction equations, calculate the energy change of the reaction at 25 °C and 1.00 bar. Sn (s) + Cl2 (g) - - - > SnCl4 (l) + H (KJmol) - 511.3.