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Ch.13 - Solutions & Their Properties
McMurry - Chemistry 8th Edition
McMurry8th EditionChemistryISBN: 9781292336145당신이 사용하는 게 아니라요?교과서 변경
모든 교과서McMurry 8th EditionCh.13 - Solutions & Their Properties문제 66
13장, 문제 66

What is the mass percent concentration of the following solutions? (a) Dissolve 0.655 mol of citric acid, C6H8O7, in 1.00 kg of water. (b) Dissolve 0.135 mg of KBr in 5.00 mL of water. (c) Dissolve 5.50 g of aspirin, C9H8O4, in 145 g of dichloromethane, CH2Cl2.

검증된 단계별 안내
1
Step 1: Understand the concept of mass percent concentration, which is defined as the mass of solute divided by the total mass of the solution, multiplied by 100%. The formula is: \( \text{Mass percent} = \left( \frac{\text{mass of solute}}{\text{mass of solute} + \text{mass of solvent}} \right) \times 100\% \).
Step 2: For part (a), calculate the mass of citric acid using its molar mass. The molar mass of citric acid (C6H8O7) is calculated by adding the atomic masses of its constituent atoms: \( 6 \times 12.01 + 8 \times 1.01 + 7 \times 16.00 \). Multiply the molar mass by the number of moles (0.655 mol) to find the mass of citric acid.
Step 3: For part (a), add the mass of citric acid to the mass of water (1.00 kg or 1000 g) to find the total mass of the solution. Use the mass percent formula to calculate the mass percent concentration.
Step 4: For part (b), convert the mass of KBr from milligrams to grams (1 mg = 0.001 g). Add this mass to the mass of water (5.00 mL of water is approximately 5.00 g, assuming the density of water is 1 g/mL) to find the total mass of the solution. Use the mass percent formula to calculate the mass percent concentration.
Step 5: For part (c), add the mass of aspirin (5.50 g) to the mass of dichloromethane (145 g) to find the total mass of the solution. Use the mass percent formula to calculate the mass percent concentration.

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Mass Percent Concentration

Mass percent concentration is a way to express the concentration of a solute in a solution, calculated as the mass of the solute divided by the total mass of the solution, multiplied by 100. This measurement provides a clear understanding of how much solute is present relative to the total mass, which is essential for comparing concentrations in different solutions.
추천 영상:
가이드 코스
00:38
Mass Percent Calculation

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is crucial for converting between moles and grams when calculating concentrations, as it allows for the determination of how much solute is present in a given mass of solution, facilitating the calculation of mass percent concentration.
추천 영상:
가이드 코스
02:11
Molar Mass Concept

Solution Preparation

Solution preparation involves dissolving a solute in a solvent to create a homogeneous mixture. Understanding the amounts of solute and solvent used is vital for accurately calculating concentrations, as the final concentration depends on both the mass of the solute and the total volume or mass of the solution.
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가이드 코스
01:39
Solution Components
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