Chemistry Test Inorganic Chemistry 2 — Questions and Answers
Question 1: Which of the following oxides is amphoteric?
- Na2O
- Al2O3 (Correct answer)
- SO3
- CaO
Correct answer: Al2O3
Al2O3 is amphoteric, reacting with both acids and bases to form salts and water.
Question 2: What is the oxidation state of chromium in K2Cr2O7?
- +3
- +4
- +6 (Correct answer)
- +7
Correct answer: +6
In K2Cr2O7, potassium is +1 and oxygen is -2, so chromium must be +6 to balance the charge.
Question 3: Which gas is produced when copper reacts with concentrated nitric acid?
- NO
- NO2 (Correct answer)
- N2O
- NH3
Correct answer: NO2
Copper reacts with concentrated HNO3 to produce NO2 (nitrogen dioxide), a brown gas.
Question 4: The VSEPR geometry of the SF6 molecule is:
- Tetrahedral
- Trigonal bipyramidal
- Octahedral (Correct answer)
- Square planar
Correct answer: Octahedral
SF6 has 6 bonding pairs and no lone pairs, giving it an octahedral geometry.
Question 5: Which of the following is a Lewis acid?
- NH3
- H2O
- BF3 (Correct answer)
- OH-
Correct answer: BF3
BF3 is a Lewis acid because it has an empty p orbital and can accept an electron pair.
Question 6: Which type of crystal structure does NaCl adopt?
- Body-centered cubic
- Face-centered cubic
- Wurtzite
- Rock salt (Correct answer)
Correct answer: Rock salt
NaCl adopts the rock salt structure, where each ion is octahedrally coordinated by six of the opposite ion.
Question 7: What is the coordination number of iron in [Fe(CN)6]4-?
- 4
- 5
- 6 (Correct answer)
- 8
Correct answer: 6
Iron is surrounded by 6 cyanide ligands in [Fe(CN)6]4-, giving it a coordination number of 6.
Chemistry Test Inorganic Chemistry 2
Which of the following oxides is amphoteric?