Question

1. which of the atoms of period 3 attracts a shared pair of electrons more strongly than phosphorus? (a) sodium (b) chlorine (c) calcium (d) arsenic. 32. which one of the following elements is chemically most similar to phosphorus? (a) silicon (b) sulfur (c) carbon (d) nitrogen. 33. which one of the following elements is most likely to form a positive ion? (a) oxygen (b) potassium (c) phosphorus (d) chlorine. 34. the elements of period 3 are similar in that they all have the same number of: (a) occupied principal energy levels (b) protons in the nucleus (c) 3p electrons (d) valence electrons. 35. which one of the following elements is most likely to form a negative ion? (a) chlorine (b) beryllium (c) carbon (d) lithium. 36. in the ground state, what is the number of valence electrons of the elements in group 17? (a) 5 (b) 6 (c) 7 (d) 8 37. the alkali metals all have the same: (a) covalent atomic radius (b) ionization energy (c) electronegativity (d) number of valence electrons. 38. the atoms of the most active nonmetals have: (a) small covalent atomic radii and high ionization energies. (b) small covalent atomic radii and low ionization energies. (c) large covalent atomic radii and low ionization energies. (d) large covalent atomic radii and high ionization energies. 39. the alkaline earth metal that has the largest covalent atomic radius is found in period: (a) 1 (b) 2 (c) 6 (d) 7. 40. which of the following ions has the smallest radius? (a) k+ (b) li+ (c) na+ (d) rb+. 41. an element that has both a high ionization energy and a high electronegativity is most likely to be a: (a) metal (b) nonmetal (c) semimetal (d) noble gas. 42. within a family of elements, as atomic number increases, covalent atomic radius increases. which of the following statements is the best explanation for this? (a) the number of occupied energy levels increases. (b) the number of occupied energy levels decreases. (c) the charge on the nucleus increases. (d) the charge on the nucleus decreases. 43. elements that have similar properties have: (a) nearly the same atomic mass (b) the same number of protons (c) the same number of valence electrons (d) the same number of total electrons.

Explanation:

• 31: Chlorine (Cl) is more electronegative than phosphorus (P). Electronegativity increases across a period. Sodium (Na) is a metal with low electronegativity, calcium (Ca) is in period 4, and arsenic (As) is in period 4.
• 32: Nitrogen (N) is in the same group (Group 15) as phosphorus (P). Elements in the same group have similar chemical properties. Silicon (Si) is in Group 14, sulfur (S) is in Group 16, and carbon (C) is in Group 14.
• 33: Potassium (K) is an alkali metal. Alkali metals easily lose an electron to form a positive ion. Oxygen (O), phosphorus (P), and chlorine (Cl) are non - metals that tend to gain electrons.
• 34: Elements in the same period have the same number of occupied principal energy levels. Protons in the nucleus increase across a period, 3p electrons are not the same for all period 3 elements, and valence electrons increase across a period.
• 35: Chlorine (Cl) is a non - metal that gains an electron to form a negative ion. Beryllium (Be) and lithium (Li) are metals that form positive ions, and carbon (C) usually forms covalent bonds.
• 36: Group 17 elements (halogens) have 7 valence electrons in the ground state.
• 37: Alkali metals (Group 1) all have 1 valence electron. They have different covalent atomic radii, ionization energies, and electronegativities.
• 38: The most active nonmetals (halogens) have small covalent atomic radii (due to increased nuclear charge across a period) and high ionization energies (difficult to lose electrons as they want to gain electrons).
• 39: The covalent atomic radius increases down a group. Among alkaline earth metals (Group 2), the element in Period 6 (barium) has a larger radius than those in lower periods.
• 40: The ionic radius decreases as you go up a group. Li⁺ is higher up in Group 1 than Na⁺, K⁺, and Rb⁺.
• 41: Nonmetals have high ionization energies (difficult to lose electrons) and high electronegativities (attract electrons). Metals have low ionization energies, semimetals have intermediate properties, and noble gases have very high ionization energies but are not very electronegative (except for some like xenon in some compounds).
• 42: As atomic number increases within a family (group), the number of occupied energy levels increases (e.g., from F to I in Group 17), which causes the covalent atomic radius to increase. The charge on the nucleus also increases, but the effect of increasing energy levels is more significant for radius increase.
• 43: Elements with similar properties (in the same group) have the same number of valence electrons. Atomic mass, number of protons, and total electrons are different for different elements in a group.

Answer:

1. B. Chlorine
2. D. Nitrogen
3. B. Potassium
4. A. occupied principal energy levels
5. A. Chlorine
6. C. 7
7. D. number of valence electrons
8. A. small covalent atomic radii and high ionization energies
9. C. 6
10. B. Li+
11. B. nonmetal
12. A. The number of occupied energy levels increases
13. C. the same number of valence electrons