CHEM 103 Final Exam 2025 Latest Update 2025- 2026 Exam 80 Questions with 100% Verified Correct Answers Guaranteed A+
A certain nonmetal atom has 74 neutrons and a mass number of 127. Which element is this?
- I
- Xe
- W
- Te
- More information is needed
Exam 2 - CORRECT ANSWER: a. I
According to the metric system, 1 m = 0.001 what?
- cm
- mm
- dm
- km
- None of the above
Exam 1 - CORRECT ANSWER: d. km
Add 250.0 mL to 5.00 mL and round off the answer.
- 250 mL
- 255 mL
- 256 mL 1 / 3
- 255.0 mL
- 255.0 mL
Exam 1 - CORRECT ANSWER: d. 255.0 mL
Ammonium borate has the formula (NH₄)₃BO₃. Calculate the percent by mass for each of the elements present.
Exam 2 - CORRECT ANSWER: N₃ = 42.00
H₁₂ = 12.096
B = 10.81
O₃ =48.00
Mr (NH₄)₃BO₃ = 113.0 N = 42.00 ÷ 113.0 x 100 = 37% H = 12.096 ÷ 113.0 x 100 = 11% B = 10.81 ÷ 113.0 x 100 = 10% O = 48.00 ÷ 113.0 x 100 = 42%
An atom of palladium (Pd) and a mass number of 105. How many neutrons does it have?
- 105
- 46
- 92
- 106
- 59
Exam 2 - CORRECT ANSWER: e. 59
105 - 46 = 59 2 / 3
Balance the following reaction: C₄H₁₀ + O₂ → CO₂ + H₂O
Exam 2 - CORRECT ANSWER: 2C₄H₁₀ + 13O₂ → 8CO₂ + 10H₂O
Balance the following reaction: Co + O₂ → Co₂O₃
Exam 2 - CORRECT ANSWER: 4Co + 3O₂ → 2Co₂O₃
Balance the following reaction: KOH + H₂SO₄ → K₂SO₄ + H₂O
Exam 2 - CORRECT ANSWER: 2KOH + H₂SO₄ → K₂SO₄ + 2H₂O
Balance the following reaction: Na₃PO₄ + Ba(CIO₄)₂ → Ba₃(PO₄)₂ + NaCIO₄
Exam 2 - CORRECT ANSWER: 2Na₃PO₄ + 3Ba(CIO₄)₂ → Ba₃(PO₄)₂ + 6NaCIO₄
For the calculation (1.200 x 1.23466 x 1.0986) - 1.33, which is the correct answer?
- 0.298
- 0.3
- 0.30
- 0.2977
- 0.29
Exam 1 - CORRECT ANSWER: c. 0.30
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