Textbook Question
Which of the following processes requires the largest input of energy? (LO 6.5) (a) (b) (c) (d)
Ch.6 - Ionic Compounds: Periodic Trends and Bonding Theory
Chapter 6, Problem 6
Phosphorus has a __________ ionization energy than magnesium because __________. (LO 6.5, 6.6) (a) larger; the electron in phosphorus is in a higher n level than the electron in magnesium (b) larger; the electron in phosphorus has a higher Zeff than the electron in magnesium (c) smaller; the electron in phosphorus is in a lower n level than the electron in magnesium (d) smaller; the electron in phosphorus has a lower Zeff than the electron in magnesium
Verified step by step guidance1
Step 1: Understand the concept of ionization energy, which is the energy required to remove an electron from an atom in the gaseous state.
Step 2: Recall that effective nuclear charge (Zeff) is the net positive charge experienced by an electron in a multi-electron atom, influencing ionization energy.
Step 3: Consider the periodic trends: Ionization energy generally increases across a period from left to right due to increasing Zeff and decreases down a group due to increasing atomic size.
Step 4: Compare the positions of phosphorus and magnesium on the periodic table. Phosphorus is to the right of magnesium in the same period, suggesting a higher Zeff for phosphorus.
Step 5: Evaluate the options: Since phosphorus has a higher Zeff than magnesium, it will have a larger ionization energy, making option (b) the correct choice.
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Ionization Energy
Ionization energy is the energy required to remove an electron from an atom in its gaseous state. It generally increases across a period due to increasing nuclear charge, which attracts electrons more strongly, and decreases down a group as electrons are added to higher energy levels, which are further from the nucleus.
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01:19
Ionization Energy
Effective Nuclear Charge (Zeff)
Effective nuclear charge (Zeff) is the net positive charge experienced by an electron in a multi-electron atom. It accounts for the shielding effect of inner electrons, meaning that outer electrons feel a reduced attraction to the nucleus. A higher Zeff leads to a stronger attraction between the nucleus and the outer electrons, resulting in higher ionization energy.
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01:51Effective Nuclear Charge
Principal Quantum Number (n)
The principal quantum number (n) indicates the main energy level occupied by an electron in an atom. As n increases, the electron is located further from the nucleus, which generally results in a weaker attraction to the nucleus and lower ionization energy. Thus, electrons in higher n levels are easier to remove compared to those in lower n levels.
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02:55Principal Quantum Number
Related Practice
Textbook Question
The successive ionization energies for a second-period element are given. What is the identity of the element? (LO 6.8)Ea1 = 1402 kJ/mol Ea2 = 2856 kJ/mol Ea3 = 4578 kJ/mol Ea4 = 7475 kJ/mol Ea5 = 9445 kJ/mol Ea6 = 53,266 kJ/mol Ea7 = 64,630 kJ/mol(a) Be(b) C(c) N (d) F
Textbook Question
Which of the following processes will release the most energy? (LO 6.9)(a) (b) (c) (d)
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Textbook Question
Elements that have large negative electron affinities generally have (LO 6.10) (a) high values for Zeff and a vacancy in a valence orbital. (b) low values for Zeff and a vacancy in a valence orbital. (c) high values for Zeff and filled valence orbitals. (d) low values for Zeff and filled valence orbitals.