Part II. Multiple choice, continued (3 points each). Name:__________________ Please circle your answer. There is only one correct answer to each question. 27. What volume (mL) of 0.135 M NaOH is required to neutralize 13.7 mL of 0.129 M HCl? A) 13.1 B) 0.24 C) 14.3 D) 6.55 28. All of the orbitals in a given electron shell have the same value of the ___________ quantum number. A) principal B) azimuthal C) magnetic D) spin 29. The places where the value of Y2 is zero are called ___________. A) orbitals B) nodes C) orbits D) wave functions 30. Of the following elements, which has the largest first ionization energy? A) B B) N C) P D) Si 31. Which equation correctly represents the second ionization of phosphorous? A) P+(g) + e- à P2+(g) B) P(g) à P+(g) + e- C) P+(g) à P2+(g) + e- D) P-(g) + e- à P2-(g) 32. Which of the following does not have eight valence electrons? A) Rb+ B) Ca+ C) Xe D) Br- 33. Of the atoms below, ____________ is the least electronegative. A) Cl B) Si C) F D) Rb 34. Of the bonds below, __________ is the least polar. A) Na - S B) P - S C) Na - Cl D) Si - Cl 35. In the Lewis structure of ClF, the formal charge on Cl is ______ and the formal charge on F is ________. A) –1, -1 B) 0, -1 C) 0, 0 D) +1, -1

What is the balanced chemical equation for the neutralization reaction between NaOH and HCl?

NaOH + HCl → NaCl + H2O

What is the mole ratio between NaOH and HCl at the equivalence point of the neutralization reaction?

1:1

How do you calculate the moles of HCl in a solution?

moles = Molarity × Volume (in L)

How do you convert liters to milliliters?

Multiply by 1000.

What are the four quantum numbers?

Principal (n), Azimuthal (l), Magnetic (ml), Spin (ms).

What does the principal quantum number (n) indicate?

The energy level or electron shell of an electron.

What is the range of values for the azimuthal quantum number (l)?

From 0 to n-1.

What does the magnetic quantum number (ml) determine?

The orientation of the orbital in space.

What are the possible values for the spin quantum number (ms)?

+1/2 or -1/2.

What is a node in quantum mechanics?

A point where the wave function has a value of zero, indicating zero probability of finding an electron.

What is ionization energy?

The energy required to remove an electron from a gaseous atom or ion.

How does ionization energy trend across a period and down a group?

Increases across a period and decreases down a group.

Why does nitrogen have a higher first ionization energy than expected?

Because of its stable half-filled p subshell.

What is the general form for the second ionization of an element X?

X^+(g) → X^{2+}(g) + e^-.

What are valence electrons?

Electrons in the outermost shell of an atom.

What configuration does Rb+ have after losing its valence electron?

The same electron configuration as Krypton (Kr).

What is the trend for electronegativity across a period and down a group?

Increases across a period and decreases down a group.

Which element is the least electronegative: Rb, Ca, or Kr?

Rb (Rubidium).

What determines bond polarity?

The difference in electronegativity between two atoms in a bond.

Which bond has the smallest difference in electronegativity: P-S, O-F, or H-Cl?

P-S (Phosphorus-Sulfur).

What is formal charge?

The charge assigned to an atom in a molecule, assuming electrons in bonds are shared equally.

How is formal charge calculated?

Formal Charge = (Valence electrons) - (Non-bonding electrons) - (1/2 Bonding electrons).

What are the formal charges on Cl and F in ClF?

Both Cl and F have a formal charge of 0.