Ch.6 - Gases

Tro - Chemistry: A Molecular Approach 6th Edition

Tro6th EditionChemistry: A Molecular ApproachISBN: 9780137832217당신이 사용하는 게 아니라요?교과서 변경

Tro 6th Edition

Ch.6 - Gases

문제 107

6장, 문제 107

The mass of an evacuated 255 mL flask is 143.187 g. The mass of the flask filled with 267 torr of an unknown gas at 25 °C is 143.289 g. Calculate the molar mass of the unknown gas.

검증된 단계별 안내

Calculate the mass of the unknown gas by subtracting the mass of the evacuated flask from the mass of the flask filled with the gas: \( \text{mass of gas} = 143.289 \text{ g} - 143.187 \text{ g} \).

Convert the pressure from torr to atm using the conversion factor: \( 1 \text{ atm} = 760 \text{ torr} \).

Convert the temperature from Celsius to Kelvin using the formula: \( T(\text{K}) = T(\text{°C}) + 273.15 \).

Use the ideal gas law \( PV = nRT \) to solve for the number of moles \( n \) of the gas, where \( P \) is the pressure in atm, \( V \) is the volume in liters, \( R \) is the ideal gas constant \( 0.0821 \text{ L atm mol}^{-1} \text{ K}^{-1} \), and \( T \) is the temperature in Kelvin.

Calculate the molar mass of the gas using the formula: \( \text{Molar mass} = \frac{\text{mass of gas}}{n} \), where \( n \) is the number of moles calculated in the previous step.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

주요 개념

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

Ideal Gas Law

The Ideal Gas Law relates the pressure, volume, temperature, and number of moles of a gas through the equation PV = nRT. This law is essential for understanding how gases behave under different conditions and is used to derive the molar mass of a gas when its pressure, volume, and temperature are known.

Molar Mass Calculation

Molar mass is defined as the mass of one mole of a substance, typically expressed in grams per mole (g/mol). To calculate the molar mass of the unknown gas, the mass difference between the empty flask and the flask filled with gas is divided by the number of moles of gas, which can be determined using the Ideal Gas Law.

Gas Density

Gas density is the mass of a gas per unit volume, often expressed in grams per liter (g/L). In this problem, the density of the unknown gas can be derived from the mass of the gas and the volume of the flask, which is crucial for calculating the molar mass using the relationship between density, molar mass, and the Ideal Gas Law.

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교과서 질문

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