Build a molecule of water (H2O) starting from its atoms. a. Atomic structure. Write down the electron configuration of H°and 1g0º. Then draw a Bohr Model for each atom. Label the nucleus, the number of protons and neutrons, the inner electrons, and the valence electrons. Use the following example as a guide: 12 1s? 2s? 2p? Nucleus: 6 protons 6 neutrons Energy level 1: 2 electrons Inner electrons Energy level 2: 4 electrons Valence electrons b. Draw the Lewis structure of water. Determine the number of electron dense areas, the electron-pair geometry, and the molecular geometry. c. Label each bond as polar or nonpolar. Add arrows to the Lewis structure to depict the direction of polarity for each bond, then draw an arrow to show the polarity of the molecule as a whole.

Predict and test the behavior of a particles fired at a plum pudding model atom. Predict the paths taken by a particles that are fired at atoms with a Thomson’s plum pudding model structure. Explain why you expect the particles to take these paths. If a particles of higher energy than those in (a) are fired at plum pudding atoms, predict how their paths will differ from the lower-energy a particle paths. Explain your reasoning. Now test your predictions from (a) and (b). Open the Rutherford Scattering simulation (http://openstaxcollege.org/I/16PhetScatter) and select the Plum Pudding Atom tab. Set Alpha Particles Energy to mm, and select show traces. Click on the gun to start firing a particles. Does this match your prediction from (a)? If not, explain why the actual path would be that shown in the simulation. Hit the pause button, or Reset All. Set Alpha Particles Energy to max, and start firing a particles. Does this match your prediction from (b)? If not, explain the effect of increased energy on the actual paths as shown in the simulation.

What refinements had to be made in Daltons atomic theory to account for Gay-Lussacs results on the combining volumes of gases?

How are the Bohr model and the Rutherford model of the atom similar? How are they different?

Give electron configurations according to the Bohr model for each of the following elements. Try to not use Figure 3.11, but instead determine the configuration based on your knowledge of the number of electrons in each atom and the maximum number of electrons in each Bohr orbit. Indicate which of these elements you expect to be the most reactive and the least reactive. a. B b. Si c. Ca d. F e. Ar

Characterize the Bohr model of the atom. In the Bohr model, what do we mean when we say something is quantized? How does the Bohr model of the hydrogen atom explain the hydrogen emission spectrum? Why is the Bohr model fundamentally incorrect?

The contributions of J. J. Thomson and Ernest Rutherford led the way to todays understanding of the structure of the atom. What were their contributions?

A chemistry instructor makes the following claim: Consider that if the nucleus were the size of a grape, the electrons would be about 1 mile away on average. Is this claim reasonably accurate? Provide mathematical support.

Your friend tells you about an article that he read in a tabloid that reported the discovery of a new form of carbon containing eight protons in the nucleus of its atoms. He claims that scientists are eager to explore the properties of this new form of carbon. What is wrong with the tabloid's claim? a. Nothing. The claim is believable. b. The claim must be false because an atom with eight protons would be oxygen, which is already known. c. The claim must be false because all forms of carbon are already known.

Give electron configurations according to the Bohr model for each of the following elements. Indicate which of these elements you expect to be the most reactive and the least reactive. a. He b. Al c. Be d. Ne e. O