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How many grams of solid CaCO3 are needed to make 600 mL of a 35 M solution? The atomic masses for the elements are as follows: Ca = 40.1 g/mol; C = 12.01 g/mol; O = 16.00 g/mol.
- A. 18.3 g
- B. 19.7 g
- C. 21.0 g
- D. 24.2 g
Correct Answer: B
Rationale: 1. First, calculate the molar mass of CaCO3 by adding the atomic masses of Ca, C, and 3 O atoms: 40.1 + 12.01 + (3 * 16.00) = 100.13 g/mol.
2. Calculate the number of moles in 600 mL of a 35 M solution: 600 mL * 35 mol/L = 21,000 mmol.
3. Convert moles to grams using the molar mass of CaCO3: 21,000 mmol * (100.13 g/mol / 1000 mmol/mol) = 2,102.73 g.
4. Therefore, you would need 19.7 g of solid CaCO3 to make 600 mL of a 35 M solution.
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- A. Superior
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- C. Medial
- D. Lateral
Correct Answer: A
Rationale: The correct answer is 'Superior.' 'Superior' refers to a position toward the head, while 'inferior' is the term for a position toward the feet. In the given example, the hand belongs to the superior extremity, which includes structures closer to the head. 'Inferior' is incorrect as it refers to a position away from the head or toward the feet. 'Medial' describes a position closer to the midline of the body, while 'lateral' refers to a position farther away from the midline.
Which term describes a position closer to the center of the body?
- A. Distal
- B. Proximal
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- D. Medial
Correct Answer: B
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What is a submicroscopic entity that is considered nonliving because it lacks cellular structure and consists of nucleic acids encapsulated in a protein coat called a capsid?
- A. Bacteria
- B. Fungus
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- D. Protozoa
Correct Answer: C
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Correct Answer: C
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Find the lowest coefficients that will balance the following combustion equation: __C H + __O2 → __CO2 + __H2O
- A. 1:5:5:2
- B. 4:10:20:8
- C. 2:9:10:4
- D. 2:5:10:4
Correct Answer: C
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