MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Transcription

1 CHM 210 Chemistry Homework #2 Atoms and Elements (Ch. 3) Due: MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Helium is a(n) A) heterogeneous mixture. B) electron. C) element. D) homogeneous mixture. E) compound. 2) Air is a(n) A) homogeneous mixture. B) compound. C) element. D) heterogeneous mixture. 3) Coins in a piggy bank is a(n) A) element. B) homogeneous mixture. C) heterogeneous mixture. D) compound. 4) The primary substances of which all other things are composed are A) molecules. B) protons. C) electrons. D) compounds. E) elements. 5) Au is the symbol for A) gold. B) silver. C) aluminum. D) sodium. E) argon. Select the correct symbol for the element named. 6) aluminum A) Am B) Au C) Sn D) Ag E) Al 7) iron A) Ir B) FE C) In D) Fs E) Fe 8) sodium A) Au B) Na C) Sm D) So E) No 9) potassium A) K B) P C) Ko D) Po E) Pt 10) silver A) Ag B) S C) AG D) Si E) Au 1

2 11) Ca is the symbol for A) copper. B) calcium. C) cadmium. D) carbon. E) cobalt. 12) What elements are in hydroxyapatite, Ca5(PO4)3OH, a major compound in human bones and teeth? A) calcium, phosphorous, oxygen, helium B) calcium, phosphorous, oxygen, hydrogen C) carbon, potassium, oxygen, helium D) carbon, potassium, oxygen, hydrogen E) carbon, phosphorous, oxygen, helium 13) Which of the following is a characteristic of the modern periodic table? A) The elements in each group have similar chemical properties. B) The A groups contain the transition elements. C) A period is a column on the periodic table. D) A group is a horizontal row on the periodic table. E) The B groups contain the representative elements. 14) Which of the following properties is NOT a characteristic of the Group 1A(1) elements (alkali metals)? A) They are good conductors of heat. B) Most of them are liquids at room temperature. C) They are good conductors of electricity. D) They are shiny. E) They react vigorously with water. 15) The Group 8A(18) elements A) are unreactive and are rarely found in combination with other elements. B) are good conductors of electricity. C) are liquids at room temperature. D) react vigorously with water. E) melt at high temperatures. 16) Which of the following is a characteristic of nonmetals? A) good conductors of heat B) good conductors of electricity C) malleable D) low melting points E) shiny 17) Which of the following elements is a noble gas? A) chlorine B) oxygen C) bromine D) argon E) nitrogen 18) The smallest particle of an element that retains the characteristics of the element is a(n) A) neutron. B) electron. C) nucleus. D) atom. E) proton. 19) Which of the following descriptions of a subatomic particle is correct? A) A proton has a positive charge and a mass of approximately 1 amu. B) A neutron has no charge and its mass is negligible. C) An electron has a negative charge and a mass of approximately 1 amu. D) A neutron has a positive charge and a mass of approximately 1 amu. E) A proton has a positive charge and a negligible mass. 2

3 20) In an atom, the nucleus contains A) an equal number of protons and electrons. B) only neutrons. C) all the protons and neutrons. D) only protons. E) all the protons and electrons. 21) The atomic number of an atom is equal to the number of A) neutrons plus protons. B) electrons plus protons. C) protons. D) nuclei. E) neutrons. 22) What is the mass number of an atom of potassium that has 20 neutrons? A) 59 B) 15 C) 35 D) 39 E) 19 23) Consider a neutral atom with 30 protons and 34 neutrons. The atomic number of the element is A) 32. B) 30. C) 34. D) 64. E) ) Consider a neutral atom with 30 protons and 34 neutrons. The mass number for this atom is A) 94. B) 32. C) 34. D) 64. E) ) How many protons are in an isotope of sodium with a mass number of 25? A) 32 B) 11 C) 25 D) 15 E) 14 26) Which of the following gives the correct numbers of protons, neutrons, and electrons in a neutral atom of Sn? A) 50 protons, 68 neutrons, 50 electrons B) 118 protons, 118 neutrons, 50 electrons C) 118 protons, 50 neutrons, 118 electrons D) 50 protons, 50 neutrons, 50 electrons E) 68 protons, 68 neutrons, 50 electrons 27) Isotopes are atoms of the same element that have A) the same atomic number but different numbers of neutrons. B) different atomic numbers. C) the same atomic numbers but different numbers of protons. D) the same atomic numbers but different numbers of electrons. E) the same atomic mass but different numbers of protons. 28) The correct symbol for the isotope of potassium with 22 neutrons is A) P. B) K. C) K. D) P. E) K. 3

4 29) Which of the following is NOT true for the atoms 13N, 14N, and 15N? A) They all have 7 electrons. B) They all have the same mass number. C) They all have 7 protons. D) They are isotopes. E) They all have the same atomic number. 30) The elements lithium, sodium, and potassium A) have the same mass number. B) are isotopes of each other. C) have the same number of neutrons. D) are in the same period of elements. E) are in the same group. 31) The electron arrangement of any particular atom shows A) the number of electrons in each energy level. B) the number of isotopes possible. C) a diagram of an atomic nucleus. D) the maximum number of electrons each energy level can hold. E) a description of the shape of each electron energy level. 32) What is the element with the electron arrangement 2,8,7? A) Ar B) S C) Cl D) F E) Be 33) What is the electron energy level arrangement for aluminum? A) 2,8,8 B) 2,8,3 C) 2,8,5 D) 2,8,7 E) 2,8,10 34) The number of electrons in the outer energy level of a neutral atom of boron (atomic number 5) is A) 10. B) 3. C) 2. D) 8. E) 5. 35) The element in this list with chemical properties similar to magnesium is A) boron. B) chlorine. C) carbon. D) strontium. E) sodium. 36) The number of valence electrons found in an atom of a Group A element is equal to A) its atomic number. B) its mass number. C) eight minus the group number. D) its group number. E) eight. 37) Valence electrons are electrons located A) in the innermost energy level of an atom. B) in the outermost energy level of an atom. C) in the first three shells of an atom. D) throughout the atom. E) in the nucleus of an atom. 4

5 38) In an electron-dot structure of an element, the dots are used to represent A) all of the electrons in the atom. B) the electrons that the element will gain when it forms a compound. C) the electron arrangement. D) only the electrons that will participate in bond formation. E) the valence electrons. 39) The number of dots in the electron dot structure of nitrogen is A) one. B) five. C) two. D) three. E) four. 40) The number of dots in the electron dot structure of carbon is A) three. B) five. C) four. D) two. E) one. 41) Which of the following is the correct electron-dot structure for carbon? A) B) C) D) E) 42) The atomic size of atoms A) decreases going down within a group. B) does not change going down within a group. C) increases going down within a group. D) increases going across a period. 5