26. explain what distinguishes the atoms of one element from the atoms of another? 27. compare and contrast…

26. explain what distinguishes the atoms of one element from the atoms of another? 27. compare and contrast how do the isotopes of a given element differ from one another? 28. explain how is atomic mass calculated? 29. identify what equation tells you how to calculate the number of neutrons in an atom? 30. compare how is atomic number different from mass number? 31. use models what does the number represent in the isotope platinum - 194? 32. explain the atomic masses of elements are generally not whole numbers. explain why. 33. identify which of argons three isotopes is most abundant: argon - 36, argon - 38, or argon - 40? (hint: the atomic mass of argon is 39.948 amu.) 34. calculate list the number of protons, neutrons, and electrons in each pair of isotopes. a. ³li, ⁷li b. ⁴⁰ca, ⁴⁴ca c. ⁷⁶se, ⁸⁰se

26. explain what distinguishes the atoms of one element from the atoms of another? 27. compare and contrast how do the isotopes of a given element differ from one another? 28. explain how is atomic mass calculated? 29. identify what equation tells you how to calculate the number of neutrons in an atom? 30. compare how is atomic number different from mass number? 31. use models what does the number represent in the isotope platinum - 194? 32. explain the atomic masses of elements are generally not whole numbers. explain why. 33. identify which of argons three isotopes is most abundant: argon - 36, argon - 38, or argon - 40? (hint: the atomic mass of argon is 39.948 amu.) 34. calculate list the number of protons, neutrons, and electrons in each pair of isotopes. a. ³li, ⁷li b. ⁴⁰ca, ⁴⁴ca c. ⁷⁶se, ⁸⁰se

Answer

Explanation:

Step1: Recall atomic - related concepts

Atomic number is the number of protons in an atom's nucleus. Atomic mass is the sum of protons and neutrons. Isotopes are atoms of the same element with different numbers of neutrons.

Step2: Answer question 26

The number of protons distinguishes the atoms of one element from another. Each element has a unique number of protons (atomic number).

Step3: Answer question 27

Isotopes of a given element differ in the number of neutrons. Since neutrons contribute to mass, isotopes have different atomic masses.

Step4: Answer question 28

Atomic mass is calculated by adding the number of protons and neutrons in the nucleus of an atom.

Step5: Answer question 29

The number of neutrons in an atom can be found by subtracting the atomic number (number of protons) from the mass number.

Step6: Answer question 30

The atomic number is the number of protons, while the mass number is the sum of protons and neutrons. So the mass number is always greater than or equal to the atomic number.

Step7: Answer question 31

The number in an isotope's name (e.g., platinum - 194) represents the mass number, which is the sum of protons and neutrons in the atom.

Step8: Answer question 32

The atomic masses of elements are generally not whole numbers because elements often exist as a mixture of isotopes, and the atomic mass is a weighted - average of the masses of these isotopes.

Step9: Answer question 33

Argon - 40 is the most abundant isotope of argon because the atomic mass of argon (39.948 amu) is closest to 40, indicating that the isotope with a mass number of 40 is the most prevalent.

Step10: Answer question 34

a. For (^6Li) and (^7Li):

  • Protons: Both are lithium, so 3 protons each.
  • Neutrons: For (^6Li), (6 - 3=3) neutrons; for (^7Li), (7 - 3 = 4) neutrons.
  • Electrons: 3 electrons each (since neutral atoms have equal number of protons and electrons). b. For (^{40}Ca) and (^{44}Ca):
  • Protons: Both are calcium, so 20 protons each.
  • Neutrons: For (^{40}Ca), (40 - 20=20) neutrons; for (^{44}Ca), (44 - 20 = 24) neutrons.
  • Electrons: 20 electrons each. c. For (^{76}Se) and (^{80}Se):
  • Protons: Both are selenium, so 34 protons each.
  • Neutrons: For (^{76}Se), (76 - 34 = 42) neutrons; for (^{80}Se), (80 - 34=46) neutrons.
  • Electrons: 34 electrons each.

Answer:

  1. The number of protons distinguishes the atoms of one element from another.
  2. Isotopes of a given element differ in the number of neutrons.
  3. Atomic mass is calculated by adding the number of protons and neutrons in the nucleus of an atom.
  4. The number of neutrons in an atom can be found by subtracting the atomic number from the mass number.
  5. The atomic number is the number of protons, and the mass number is the sum of protons and neutrons, so the mass number is greater than or equal to the atomic number.
  6. The number in an isotope's name represents the mass number.
  7. The atomic masses of elements are generally not whole numbers because elements are often a mixture of isotopes and the atomic mass is a weighted - average of the masses of these isotopes.
  8. Argon - 40 is the most abundant isotope of argon because the atomic mass of argon is closest to 40.
  9. a. (^6Li): 3 protons, 3 neutrons, 3 electrons; (^7Li): 3 protons, 4 neutrons, 3 electrons. b. (^{40}Ca): 20 protons, 20 neutrons, 20 electrons; (^{44}Ca): 20 protons, 24 neutrons, 20 electrons. c. (^{76}Se): 34 protons, 42 neutrons, 34 electrons; (^{80}Se): 34 protons, 46 neutrons, 34 electrons.