What particles form the nucleus of an atom? CHEMISTRY OLYMPICS 2nd 6 weeks

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1 CHEMISTRY OLYMPICS 2nd 6 weeks Class Battle Between: Bauer, Cannon, Hermsdorf, Lawton, and Muller What particles form the nucleus of an atom? A) protons and neutrons B) electrons only C) neutrons and electrons D) protons and electrons E) none of the above What is the smallest particle of an element that retains the properties of that element? A) a proton B) an atom C) a molecule D) a neutron E) an electron Which of the following is NOT a part of Dalton s atomic theory? A) Atoms that combine do so in simple whole-number ratios B) Atoms of the same element are alike in mass and size C) Atoms are always in motion D) All elements are composed of atoms Who was the first person to suggest the idea of atoms, in the fourth century B.C.? A) Galileo B) Atomos C) Thomson D) Dalton E) Democritus In which of the following sets are the symbol of the element, the number of protons, and the number of electrons given correctly? A) Cs, 55 protons, electrons B) He, 4 protons, 4 electrons C) Zn, 30 protons, 60 electrons D) F, 19 protons, 19 electrons E) In, 49 protons, 49 electrons

2 Which of these statements is FALSE? A) The nucleus of an atom is positively charged. B) Protons have a positive charge. C) The neutron is found in the nucleus of an atom. D) Electons are negativley charged and have a mass of 1 amu. What does the 84 in the name krypton-84 represent? A) The mass number B) The sum of the protons and electrons C) The atomic number D) None of these Consider an element Z that has two naturally occurring isotopes with the following percent abundances: the isotope with a mass number of 20 is 25% abundant; the isotope with a mass number of 22 is 75% abundant. What is the average atomic mass for element Z? A) 21.0g B) 42.0g C) 21.5g D) 2.0g E) 20.5g Which of these elements does not exist as a diatomic molecule? A)I B) C) D) Select the correct statement about subatomic particles A) Electrons, protons, and neutrons all have the same mass. B) Electrons are negatively charged and are the heaviest subatomic particles. C) The mass of a neutron nearly equals the mass of a proton. D) Neutrons have no charge and are the lightest subatomic particle. E) Protons are positively charged and the lightest subatomic particle. What are the Group A elements known as? A) Representative elements B) Transition elements C) Inner transition elements D) Metallic elements E) Periodic elements

3 Of the elements Pt, Sc, V, Li, and Kr, which is a nonmetal? A) Kr B) Li C) V D) Pt E) Sc The modern periodic table is arranged in order of increasing atomic. A) Radius B) Mass C) Number D) Charge Which subatomic particle plays the greatest part in determining the physical and chemical properties of an element? A) muon B) quark C) proton D) electron E) neutron How many energy sublevels are there in the second principal energy level? A) 3 B) 4 C) 1 D) 2 E) 5 The principal quantum number indicates what property of an electron? A) position B) electron cloud shape C) speed D) energy level E) spin When an electron moves from a lower to a higher energy level, the electron. A) always doubles its energy B) absorbs a quantum of energy C) moves closer to the nucleus D) absorbs a continuously variable amount of energy

4 Which element is a transition element? A)Cesium B) Tellurium C)Tin D) Copper How many electrons does barium have to give up in order to achieve a noble-gas electron configuration? A) 1 B) 2 C) 3 D) 4 E) 5 What is a beta particle? A) A helium nucleus B) An electron C) A photon D) A hydrogen nucleus Above what number are the transuranium elements? A) 110 B) 92 C) 102 D) 82 If the half-life of sodium-24 is 15 hours, how much remains from a 10.0g sample after 60 hours? A) 2.5g B) 1.3g C).63g D) 2.5g Which of these processes results in the splitting of atoms? A) A fission reaction B) An ionizing reaction C) A fusion reaction D) A chemical reaction

5 Which cells are the most sensitive to ionizing radiation? How many protons, electrons, and neutrons does an atom with an atomic number 50 and a mass number 120 contain? A) Cells that divide slowly B) Cells that divide rapidly C) Cells that do not divide A) 70 electrons, 50 protons, and 50 neutrons B) 50 protons, 50 electrons, and 70 neutrons C) 70 neutrons, 70 protons, and 50 electrons D) 120 neutrons, 50 protons, and 70 electrons Who first arranged the elements according to atomic mass and noticed a periodic recurrence of their physical and chemical properties? A) John Dalton B) Louis Pasteur C) Henry Mosely D) Antoine Lavoisier E) Dmitri Mendeleev What is each vertical column of elements in the periodic table called? A) Transition B) List C) Group or family D) Row Which of the following categories includes the majority of the elements? A) Metalloids B) Gases C) Nonmetals D) Metals E) Liquids Which scientist developed the quantum mechanical model of the atom? A) Niels Bohr B) JJ Thompson C) Erwin Shrodinger D) Ernest Rutherford E) Albert Einstein

6 What is the next atomic orbital in the series 1s, 2s, 2p, 3s, 3p? A) 3f B) 3d C) 2f D) 2d E) 4s What is the number of electrons in the outermost energy level of an oxygen atom? A) 2 B) 4 C) 6 D) 8 E) 10 What is the basis for exceptions to the Aufbau diagram? A) Some elements have unusual atomic orbitals. B) Electron configurations are only probable. C) Electron spins are more important than energy levels in determining electron configuration. D) Filled and half-filled energy sublevels are more stable than partially-filled ones. What orbital is filled when iodine gains an electron to become a negative ion? A) 6s B) 5p C) 4p D) 4d What is the name given to the electrons in the highest occupied energy level of an atom? A) Cations B) Anions C) Affinity Electrons D) Valence Electrons E) Orbital Electrons Compared with the electronegativities of the elements at the left end of a particular period, the electronegativities of the elements at the right side of that same period tend to be. A) higher B) lower C) unpredictable D) the same

7 How many valence electrons does an atom of any halogen have? A) 6 B) 8 C)7 D)4 What is the maximum charge an ion is likely to have? A) 5 B) 3 C) 2 D) 6 E) 4 Which of these elements does not exist as a diatomic molecule? A) H B) F C) I D) Ne What particle is emitted in alpha radiation? A) Electron B) Photon C) Helium nucleus D) Hydrogen nucleus What does an unstable nucleus NOT do to become more stable? A) Change its number of electrons B) Rearrange its protons C) Emit radiation D) Change its number of protons and/or neutrons A) -2 B) 0 C) -1 D)+2 E)+1 What is the charge on an alpha particle?

8 Who discovered radioactivity? A) Ernest Rutherford B) George Geiger C) Antoine Becquerel D) Marie Curie E) Albert Einstein What does gamma radiation consist of? A) Helium nuclei B) Electrons C) Photons D) Hydrogen nuclei The most penetrating form of radiation is. A) Gamma radiation B) Visible radiation C) Alpha radiation D) Beta radiation How are the number of neutrons in the nucleus of an atom calculated? A) Subtract the number of electrons from the number of protons B) Add the number of electrons and protons together C) Subtract the number of protons from the mass number D) Add the mass number to the number of electrons How do the isotopes hydrogen-1 and hydrogen-2 differ? A) Hydrogen-1 has no protons; hydrogen-2 has one. B) Hydrogen-2 has two protons; hydrogen-1 has one. C) Hydrogen-2 has one more electron than hydrogen-1 D) Hydrogen-2 has one neutron; hydroge-1 has none A mystery element Q is a nonlustrous solid and a poor conductor of electricity. To what category of elements does it belong? A) Metals B) Nonmetals C) Metalloids D) Transition metals E) Semimetals

9 The term used to describe an atom s tendency to attract electrons to itself when it is chemically combined with another element. A) Electronegativity B) Electronation C) Electron affinity D) Electrochemical attraction E) Electrolysis Who discovered the electron? A) John Dalton B) Albert Einstein C) JJ Thompson D) Niels Bohr E) Ernest Rutherford What types of atomic orbitals are in the third principal energy level? A) s and p only B) s, p, and d only C) p, d, and f only D) s, p, d, and f E) p and d only Which of the following energy levels has the lowest energy? A) 4p B) 4s C) 4f D) 3d What is the maximum number of electrons in the third principal energy level? A) 18 B)2 C) 32 D) 8 What is the maximum number of d orbitals in a principal energy level? A) 2 B) 5 C) 1 D) 3 E) 10

10 The energy required to remove an electron froma gaseous atom is called the. A) Heat of vaporization B) Polarization energy C) Ionization energy D) Excitation energy E) Electrolytic energy Which of the following elements has the lowest electronegativity? A) Bromine B) Fluorine C) Lithium D) Carbon How does the energy of an electron change when the electron moves closer to the nucleus? A) It increases B) It stays the same C) It decreases If three electrons are available to fill three empty 2p atomic orbitalsm how will the electrons be distributed in the three orbitals? A) Three in one orbital, none in the other two B) Two electrons in one orbital, one in another, none in the third C) One electron in each orbital What did Rutherford s experiment demonstrate? A) that electrons orbit the nucleus B) that atoms are made of positively and negatively charged particles C) that most of an atom s mass is concentrated in a relatively small portion of the atom s entire volume D) that all neutrons are located in the nucleus Which of the following states that no more than two electrons can occupy an atomic orbital and that two electrons in the same orbital must have opposite spins? A) the Aufbau principle B) Hund s rule C) Dalton s theory D) the Paulie exclusion principle

11 What is the charge of a particle having 9 protons and 10 electrons? A) 0 B) 1+ C) 1- D) 2+ E) 2- The electron configuration of a fluoride ion, F-, is. A) the same as that of a neon atom B) the same as a that of a potassium ion C) 1s 2 2s 2 2p 5 D) 1s 2 2s 2 2p 6 3s 1 In Bohr s model of the atom, where are the electrons and protons located? A) The electrons and protons move throughout the atom. B) The electrons orbit the protons, which are at the center of the atom. C) The electrons and protons are located thorughout the atom, but they are not free to move. D) The electrons occupy fixed positions around the protons, which are at the center of the atom. What element has the electron configuration 1s 2 2s 2 2p 6 3s 2 3p 2? A) Silver B) Nitrogen C) Silicon D) Selenium How does atomic radius change from left to right across a period in the periodic table? A) It first increases, then decreases B) It first decreases, then increases C) It tends to increase D) It tends to decrease E) It does not change Why is the radius of a positive ion always less than the radius of its neutral atom? A) The number of principal energy levels is always reduced B) The atomic orbitals contract all by themselves C) The nucleus pulls the remaining electrons in closer D) Electron speeds are reduced