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Ch.3 - Chemical Reactions and Reaction Stoichiometry
Brown - Chemistry: The Central Science 14th Edition
Brown14th EditionChemistry: The Central ScienceISBN: 9780134414232당신이 사용하는 게 아니라요?교과서 변경
모든 교과서Brown 14th EditionCh.3 - Chemical Reactions and Reaction Stoichiometry문제 37c
3장, 문제 37c

(c) What is the mass, in grams, of 7.70⨉1020 molecules of caffeine, C8H10N4O2?

검증된 단계별 안내
1
Determine the molar mass of caffeine (C_8H_10N_4O_2) by adding the atomic masses of all the atoms in the formula.
Calculate the number of moles of caffeine using Avogadro's number (6.022 \(\times\) 10^{23} molecules/mol) to convert molecules to moles.
Use the number of moles calculated in the previous step to find the mass in grams by multiplying it by the molar mass of caffeine.
Set up the conversion factor to go from molecules to grams, ensuring units cancel appropriately.
Perform the calculation to find the mass in grams of the given number of caffeine molecules.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
1m

주요 개념

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

Molecular Weight

Molecular weight, or molar mass, is the mass of one mole of a substance, expressed in grams per mole (g/mol). For caffeine (C8H10N4O2), the molecular weight is calculated by summing the atomic weights of all the atoms in its formula: 8 carbon (C), 10 hydrogen (H), 4 nitrogen (N), and 2 oxygen (O) atoms. This value is essential for converting between the number of molecules and mass.
추천 영상:
가이드 코스
03:45
Weight Conversion Example

Avogadro's Number

Avogadro's number, approximately 6.022 × 10^23, is the number of atoms, ions, or molecules in one mole of a substance. This constant allows chemists to relate the macroscopic scale of substances (grams) to the microscopic scale (molecules). In this question, it is used to convert the given number of caffeine molecules into moles, which can then be converted to mass.
추천 영상:
가이드 코스
02:11
Avogadro's Law

Conversion from Molecules to Grams

To find the mass of a substance from the number of molecules, one must first convert the number of molecules to moles using Avogadro's number, and then multiply the number of moles by the molecular weight. This two-step conversion is crucial for solving the problem, as it bridges the gap between the microscopic quantity of molecules and the macroscopic quantity of mass.
추천 영상:
가이드 코스
03:45
Weight Conversion Example
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