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Quarter 1 Review of Transfer of Learning Integrated Science 1.) An important piece of evidence supporting the Big Bang Theory is that all galaxies are moving away from the Earth. We know that this is true because of the Doppler Effect things moving away from us would have a longer wavelength (whether it be wavelengths of sound or light), and the faster something is moving away from us the longer the wavelength will be. For galaxies, this is shown by a shift in light wavelengths toward the long (red) side. To illustrate this, we did a project looking at how fast friends would be moving away from us when leaving a party in a radial manner. In this illustration, we would represent the earth (Milky way galaxy) and our friends would represent other galaxies. For the illustration below, let 1 cm = 10 km. Path of Friend 1 Your Path Path of Friend 2 Departure Point 1 Hour 2 Hours After 1 hour, how far is Friend 1 from you? After 2 hours, how far is Friend 1 from you? Compute the average speed at which friend 1 is moving away from you. After 1 hour, how far is Friend 2 from you? After 2 hours, how far is Friend 2 from you? Compute the average speed at which friend 2 is moving away from you. 2.) In our unit of element formation in stars we reviewed some basic properties of elements. We mentioned that an element is determined by the number of protons in its nucleus, called the atomic number. Some atoms of the same element have different numbers of neutrons in their nucleus. Two atoms of the same element with different numbers of neutrons are called isotopes. The shorthand notation for writing an isotope is by using the following guide: mass number atomic number Element symbol For example, an isotope of carbon has 8 neutrons. From the periodic table, the symbol for carbon is C. Also from the periodic table, we see it has 6 protons. The mass number for this isotope is 6 + 8 = 14. The shorthand notation for writing this isotope of carbon, then, is 146C . Some examples: Write the shorthand notation for an isotope of oxygen having 10 neutrons. Write the shorthand notation for an isotope of chlorine having 19 neutrons. In looking at the periodic table, we mentioned that the row number corresponds to the energy level of the outermost electrons. For elements in the first two columns and last 6 columns, we can easily determine the number of electrons in an elements outermost shell. For example, the element chlorine is in the third energy level and it has 7 electrons in its outermost shell. Describe the outer energy shell number and the number of electrons in the outermost shell for these elements: Aluminum (Al) Nitrogen (N) Lithium (Li) 3.) In our present chapter we are looking at how atoms combine to form compounds. We have looked at ionic and covalent compounds. Ionic compounds involve elements forming ions with a negative charge (called anions) or a positive charge (cations) by either gaining or losing electrons. Illustrate with a drawing how magnesium becomes a cation, and give its charge. Illustrate with a drawing how oxygen becomes an anion, and give its charge. Illustrate how magnesium and oxygen combine together to form an ionic compound. A second type of bond is a covalent bond, formed by atoms sharing electrons. Illustrate how two fluorine atoms, F, join together to form a covalent bond. Atoms form ions in an attempt to have their outermost shell filled with electrons. In doing this, they will have the same number of electrons as a noble gas element. List four ions that will have the same number of electrons as the noble element neon. 4.) We have just performed a lab to determine the density of a number of objects and also to calculate the average number of particles (protons and neutrons) there are per atom in a substance. For example, say that we measure the mass of a piece of the mineral olivine, Mg2SiO4, to be 15.6 grams. We find by water displacement that its volume is 4.7 cm3. a.) What is its density? b.) What is the average number of protons and neutrons per atom for olivine?