What is the symbol for this MO and how many nodal planes (nodes) does it have? The dark dots in this sketch are the nuclei. The symbol is T* and it has one nodal plane. The symbol is o* and it has no nodal planes. The symbol is T* and it has no nodal planes. The symbol is n and it has no nodal planes. The symbol is r and it has two nodal planes. The symbol is o* and it has one nodal plane. None of these he symbol is o* and it has two nodal planes. The symbol is T* and it has two nodal planes. The symbol is o and it has one nodal plane. The symbol is n and it has one nodal plane. The symbol is o and it has two nodal planes. The symbol is o and it has no nodal planes.

2. The data in the table show the amount of a 500 g sample of sodium-24 over time. Time (h) Na-24 (g) Time (h) Na-24 (g) 0 500 55 397 60 315 65 250 70 198 75 5 10 15 20 25 30 35 40 45 50 158 125 99 79 63 50 80 85 90 95 100 39 31 25 20 16 12 10 8 6 5 Make a graph of the data (remember to label all axes and title the graph). What is the half-life of sodium-24? Explain how you determined your answer. Sodium-24 decays by beta emission. Write a nuclear equation that shows the decay of sodium-24 and its products.

What are the key differences in (a) energy and (b) location of electron density between a 2s orbital and a 2px orbital. Maybe a diagram to help?

Draw an “energy level diagram” for a calcium (Ca) atom. HINT: Use the periodic table to determine the number of electrons that are present in a krypton atom. An empty (no electrons) energy level diagram for multi-electron atoms is shown on the left. Electrons are arranged (configured) into the orbitals in the way that results in the lowest possible energy. Nature does this by obeying the Aufbau Principle, the Pauli Exclusion Principle, and Hund’s Rules. See the hint from the previous question (3.2) for more details. EXPLANATION: A calcium atom has 20 protons and therefore 20 electrons. Electrons are arranged (configured) into the orbitals in the way that results in the lowest possible energy. Nature does this by obeying the Aufbau Principle, the Pauli Exclusion Principle, and Hund’s Rules. See the hint from the previous question (3.2) for more details. Note that the 4s orbital fills before the 3d orbital because the 4s orbital lower in energy than the 3d orbitals (the 3d orbitals are…