Unit 1: Atomic Structure & Properties - HW #2
Directions: Each set of lettered choices below refers to the numbered statements immediately following it. Select the one lettered choice that best fits each statement. A choice may be used once more, more than once, or not at all in each set. Which of the following has the lowest first-ionization energy? A. Cs B. Ag C. Pb D. Br E.Se
A. Cs
Directions: Each set of lettered choices below refers to the numbered statements immediately following it. Select the one lettered choice that best fits each statement. A choice may be used once more, more than once, or not at all in each set. Which one has the largest radius? A. Cs B. Ag C. Pb D. Br E. Se
A. Cs
Consider atoms of the following elements. Assume that the atoms are in the ground state. The atom that contains exactly two unpaired electrons A. S B. Ca C. Ga D. Sb E. Br
A. S
If a pure sample of an oxide of sulfur contains 40% sulfur and 60% oxygen by mass, then the empirical formula of the oxide is A. SO₃ B. SO₄ C. S₂O₆ D. S₂O₈
A. SO₃
Of the following electron configurations of neutral atoms, which represents an atom in an excited state? A. 1s² 2s² 2p⁵ B. 1s² 2s² 2p⁵ 3s² C. 1s² 2s² 2p⁶ 3s¹ D. 1s² 2s² 2p⁶ 3s² 3p² E. 1s² 2s² 2p⁶ 3s² 3p⁵
B. 1s² 2s² 2p⁵ 3s²
Atoms of Mg combine with atoms to F a compound. Atoms of which of the following elements combine with atoms of F in the same ratio? A. Li B. Ba C. Al D. Cl E. Ne
B. Ba
Na₂O 62.0g MgO 40.3g K₂O 94.2g CaO 56.1g According to the information in the table above, a 1.00 g sample of which of the following contains the greatest mass of oxygen? A. Na₂O B. MgO C. K₂O D. CaO
B. MgO
Forms monatomic ions with 2- charge in solutions A. F B. S C. Mg D. Ar E. Mn
B. S
After completing an experiment to determine gravimetrically the percentage of water in a hydrate, a student reported a value of 38%. The correct value for the percentage of water in the hydrate is 51%. Which of the following is the most likely explanation for this difference? A. Strong initial heating caused some of the hydrate sample to spatter out of the crucible. B. The dehydrate sample absorbed moisture after heating. C. The amount of the hydrate sample used was too small. D. The crucible was not heated to constant mass before use. E. Excess heating caused the dehydrate sample to decompose.
B. The dehydrate sample absorbed moisture after heating
Which of the following represents the ground state electron configuration for Mn³⁺ ion? A. 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁴ B. 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵ 4s² C. 1s² 2s² 2p⁶ 3s² 3p⁶ 3d² 4s² D. 1s² 2s² 2p⁶ 3s² 3p⁶ E. 1s² 2s² 2p⁶ 3s² 3p⁶ 3d³ 4s¹
C. 1s² 2s² 2p⁶ 3s² 3p⁶ 3d² 4s²
A sample of CaCO₃ (molar mass 100 g) was reported as being 30% Ca. Assuming no calcium was present in any impurities, the percent of CaCO₃ in the sample is A. 30% B. 40% C. 70% D. 75% E. 100%
D. 75%
Directions: Each set of lettered choices below refers to the numbered statements immediately following it. Select the one lettered choice that best fits each statement. A choice may be used once more, more than once, or not at all in each set. Which of the following has the highest electronegativity? A. Cs B. Ag C. Pb D. Br E. Se
D. Br
The elements in which of the following have most nearly the same atomic radius? A. Be, B, C, N B. Ne, Ar, Kr, Xe C. Mg, Ca, Sr, Ba D. C, P, Se, I E. Cr, Mn, Fe, Co
E. Cr, Mn, Fe, Co
