Chem 121 exam 2 Questions with Verified Solutions
Using the equations 2 Fe (s) + 3 Cl₂ (g) → 2 FeCl₃ (s) ∆H° = -800.0 kJ/mol Si(s) + 2 Cl₂ (g) → SiCl₄
(s) ∆H° = -640.1 kJ/mol Determine the enthalpy (in kJ/mol) for the reaction 3 SiCl₄ (s) + 4 Fe (s)
→ 4 FeCl₃ (s) + 3 Si (s)✔✔320.3 kJ/mol
Using the equations N₂ (g) + 3 H₂ (g) → 2 NH₃ (g) ∆H° = -91.8 kJ/mol C(s) + 2 H₂ (g) → CH₄ (g) ∆H°
= -74.9 kJ/mol H₂ (g) + 2 C(s) + N₂ (g) → 2 HCN (g) ∆H° = 270.3 kJ/mol Determine the enthalpy
(in kJ/mol) for the reaction CH₄ (g) + NH₃ (g) → HCN (g) + 3 H₂ (g).✔✔256.0 kJ/mol
Using the provided table, determine the enthalpy (in kJ/mol) for the reaction 2 K(s) + 2 H₂O(l) →
2 KOH (aq) + H₂(g)
K(s)=0
H20(l)=-285.8
KOH(aq)=-482.4
H2(g)=0✔✔-393.2 kJ/mol
What is the frequency of green light that has a wavelength of 531 nm? (c = 3.00 x 10⁸
m/s)✔✔5.65 × 10¹⁴ s⁻¹
What is the energy (in J) of a mole of photons that have a wavelength of 701 nm? (h = 6.626 ×
10⁻³⁴ J • s and c = 3.00 × 10⁸ m/s)✔✔1.70 × 10⁵ J
For which atomic orbital does n = 3 and ℓ = 1?
A) 2s
B) 3s
C) 3p
, D) 3d
E) 4d✔✔C
Complete the balanced dissociation equation for the compound below in aqueous solution. If
the compound does not dissociate, write NR after the reaction arrow.
C6H8O2(l)----->✔✔NR
Complete the balanced dissociation equation for the compound below in aqueous solution. If
the compound does not dissociate, write NR after the reaction arrow.
Al₂(SO₄)₃(s) →✔✔Al₂(SO₄)₃(s) → 2 Al³⁺(aq) + 3 SO₄²⁻(aq)
Complete the balanced molecular chemical equation for the reaction below. If no reaction
occurs, write NR after the reaction arrow.
3 KOH(aq) + AlCl₃(aq) →✔✔3 KOH(aq) + AlCl₃(aq) → Al(OH)₃(s) + 3 KCl(aq)
In the reaction between FeCl₃ and NaOH, the spectator ions are
A) Fe³⁺ and Cl⁻
B) Fe³⁺ and OH⁻
C) Na⁺ and OH⁻
D) Na⁺ and Cl⁻✔✔D.
Write the balanced NET ionic equation for the reaction when BaCl₂ and ZnSO₄ are mixed in
aqueous solution. If no reaction occurs, simply write only NR.
Ba²⁺(aq) + SO₄²⁻(aq) →✔✔Ba²⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)
Write the balanced COMPLETE ionic equation for the reaction when iron(III) chloride and
sodium sulfide are mixed in aqueous solution. If no reaction occurs, simply write only NR.
Using the equations 2 Fe (s) + 3 Cl₂ (g) → 2 FeCl₃ (s) ∆H° = -800.0 kJ/mol Si(s) + 2 Cl₂ (g) → SiCl₄
(s) ∆H° = -640.1 kJ/mol Determine the enthalpy (in kJ/mol) for the reaction 3 SiCl₄ (s) + 4 Fe (s)
→ 4 FeCl₃ (s) + 3 Si (s)✔✔320.3 kJ/mol
Using the equations N₂ (g) + 3 H₂ (g) → 2 NH₃ (g) ∆H° = -91.8 kJ/mol C(s) + 2 H₂ (g) → CH₄ (g) ∆H°
= -74.9 kJ/mol H₂ (g) + 2 C(s) + N₂ (g) → 2 HCN (g) ∆H° = 270.3 kJ/mol Determine the enthalpy
(in kJ/mol) for the reaction CH₄ (g) + NH₃ (g) → HCN (g) + 3 H₂ (g).✔✔256.0 kJ/mol
Using the provided table, determine the enthalpy (in kJ/mol) for the reaction 2 K(s) + 2 H₂O(l) →
2 KOH (aq) + H₂(g)
K(s)=0
H20(l)=-285.8
KOH(aq)=-482.4
H2(g)=0✔✔-393.2 kJ/mol
What is the frequency of green light that has a wavelength of 531 nm? (c = 3.00 x 10⁸
m/s)✔✔5.65 × 10¹⁴ s⁻¹
What is the energy (in J) of a mole of photons that have a wavelength of 701 nm? (h = 6.626 ×
10⁻³⁴ J • s and c = 3.00 × 10⁸ m/s)✔✔1.70 × 10⁵ J
For which atomic orbital does n = 3 and ℓ = 1?
A) 2s
B) 3s
C) 3p
, D) 3d
E) 4d✔✔C
Complete the balanced dissociation equation for the compound below in aqueous solution. If
the compound does not dissociate, write NR after the reaction arrow.
C6H8O2(l)----->✔✔NR
Complete the balanced dissociation equation for the compound below in aqueous solution. If
the compound does not dissociate, write NR after the reaction arrow.
Al₂(SO₄)₃(s) →✔✔Al₂(SO₄)₃(s) → 2 Al³⁺(aq) + 3 SO₄²⁻(aq)
Complete the balanced molecular chemical equation for the reaction below. If no reaction
occurs, write NR after the reaction arrow.
3 KOH(aq) + AlCl₃(aq) →✔✔3 KOH(aq) + AlCl₃(aq) → Al(OH)₃(s) + 3 KCl(aq)
In the reaction between FeCl₃ and NaOH, the spectator ions are
A) Fe³⁺ and Cl⁻
B) Fe³⁺ and OH⁻
C) Na⁺ and OH⁻
D) Na⁺ and Cl⁻✔✔D.
Write the balanced NET ionic equation for the reaction when BaCl₂ and ZnSO₄ are mixed in
aqueous solution. If no reaction occurs, simply write only NR.
Ba²⁺(aq) + SO₄²⁻(aq) →✔✔Ba²⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)
Write the balanced COMPLETE ionic equation for the reaction when iron(III) chloride and
sodium sulfide are mixed in aqueous solution. If no reaction occurs, simply write only NR.
