Atomic Structure Chapter 5 Assignment & Problem Set

Transcription

1 Atomic Structure Name Warm-Ups (Show your work for credit) Date 1. Date 2. Date 3. Date 4. Date 5. Date 6. Date 7. Date 8.

2 Atomic Structure 2 Study Guide: Things You Must Know Vocabulary (know the definition and what it means): atom element compound subatomic particle proton neutron electron atomic mass unit charge Rutherford experiment nucleus atomic number mass number atomic mass atomic symbol isotope Periodic Table period group or family metal nonmetal metalloid luster electrical conductivity ductile malleable brittle representative element transition element inner transition element alkali metal alkaline earth metal halogen noble or inert gas diatomic element Learning Objectives: the concept of the atom as the smallest unit of an element the difference between particle matter and continuous matter Dalton s atomic theory the three subatomic particles, their symbols, their relative masses, their charges, and their location within an atom the Rutherford experiment and its conclusions relative size of the nucleus compared to the size of the atom how to determine the number of protons, neutrons, and electrons, given the atomic symbol how the elements are arranged on the Periodic Table the meaning of the information given for each element on the Periodic Table what differentiates isotopes of an element how to calculate (average) atomic mass, given abundances and masses of the isotopes general properties of metals and nonmetals the location of representative, transition, and inner transition elements on the Periodic Table the special names of the Group 1, 2, 17, and 18 elements which elements are diatomic which elements are solids, liquids, and gases Key Reference Tables Periodic Table

3 Atomic Structure 3 Read Chapter 5 Complete the Reading Assignment on Periodic Table Lab 4: Isotopes: Determining Atomic Structure Warm-ups and problems will be collected before you take the test. Answer all problems in the space provided. For problems involving an equation, carry out the following steps: 1. Write the equation. 2. Substitute numbers and units. 3. Show the final answer with units. There is no credit without showing work. Composition of the Atom 1. What are the charges and relative masses of the three main subatomic particles? 2. How did the result of Rutherford's gold foil experiment differ from his expectations? 3. Rutherford's atomic theory proposed a dense nucleus surrounded by very small electrons. This implies that atoms are composed mainly of empty space. If all matter is mainly empty space, why is it impossible to walk through walls or pass your hand through your desk. 4. (Honors) Roughly speaking, the radius of an atom is 10,000 times greater than that of its nucleus. If the nucleus of an atom were magnified to the size of a basketball (radius ~30. cm) what would be the size of the atom in miles? (1 mi = 1609 m) Atomic Number and Mass Number 5. Why is an atom electrically neutral? 6. How many protons are in the nuclei of the following atoms? a. phosphorus b. aluminum c. chromium 7. How many neutrons are in each atom? a. 16 O b. 32 S c. 108 Ag Mass numbers are whole numbers but atomic masses are not whole numbers. Explain. 9. Complete this table: Atomic Number Mass Number Protons Neutrons Electrons Symbol of Element

4 Atomic Structure Complete the following table: Symbol of Atomic Element Number Mass Number Protons Electrons P 32 Mn 30 Ne Isotopes and Atomic Mass 11. How are isotopes of the same element alike? How are they different? Neutrons 12. What data must you know about the isotopes of an element to calculate the atomic mass of the element? 13. How can there be more than 1000 different atoms when there are only about 100 different elements? 14. The atomic masses of an element calculated from isotope data. Using the data below, calculate the average atomic mass of carbon. Show your work. Symbol % abundance Mass(amu) 12 6 C C (Honors) The four isotopes of lead are shown below, each with its percent by mass abundance and the composition of its nucleus. Using these data, calculate the approximate atomic mass of lead. 122n 124n 125n 126n 1.37% 26.26% 20.82% 51.55% 16. Calculate the average atomic mass of an element given the following data and then identify the element: Isotope % of Isotope Mass of Isotope (amu) A B

5 Atomic Structure 5 Periodic Table 17. Identify each element as a metal, metalloid, or nonmetal. a. gold b. silicon c. manganese d. sulfur e. barium 18. Name 2 elements that have properties similar to those of the element calcium. 19. List the metalloids. 20. List the elements called the alkaline earth metals. 21. List the elements that occur naturally as diatomic molecules. Review 22. This chapter illustrates the scientific method in action. What happens when new experimental results cannot be explained by the existing theory. 23. Oxygen and hydrogen react explosively to form water. In one reaction, 6g of hydrogen combines with oxygen to form 54g of water. How much oxygen was used? 24. How many significant figures are in each measurement? a mg b x 10 4 km c ml d kg 25. What is the mass of 5.42cm 3 of platinum? The density of platinum is 22.5g/cm Classify each as an element, a compound, or a mixture. a. sulfur c. newspaper e. cardboard b. salad oil d. orange f. apple juice 27. (Honors) Diamond and graphite are both composed of carbon atoms. The density of diamond is 3.52 g/cm3 and the density of graphite is 2.25 g/cm3. In 1955, scientists successfully turned graphite into diamond. Given their densities, imagine how this synthesis was accomplished. 28. (Honors) Lithium has two isotopes, Li-6 (atomic mass of amu) and Li7 (atomic mass of amu). The atomic mass of Lithium is amu. Calculate the percentage of each isotope.

6 Atomic Structure 6 Periodic Table: Read Chapter 5, section 5.4 pages and answer the following questions. For numerical problems, show all work. 1. What scientist organized the first Periodic Table? 2. This original Periodic Table was organized by what two criteria of the elements? How does this differ from how the Periodic Table is organized now? Original and. Current and. 3. Rows on the Periodic Table are called. Columns on the Periodic Table are called or. 4. Using the Regents reference periodic Table, which Group number (s) are: Transition metals Alkalai metals Alkaline earth metals Halogens Noble or Inert gases 5. The heavy step line on the Periodic Table separates what two general types of elements? 6. What is the general name of the elements directly touching the heavy step line (except Al)?