How many molecules are in each sample? a. 6.5 g H 2 O c. 22.1 g O 2 d. 19.3 g C 8 H 10

Hi everyone today. We have a question asking us to assume that a tablet only contains paracetamol C eight H nine N 02. And to calculate the number of paracetamol molecules in a 500 mg tablet. So we're going to start out with our 500 mg of paracetamol And then we want to change two g. So we're going to multiply By 10 to the negative 3rd g over one mg and then we are going to multiply by one mole of paracetamol, divided by The molar mass of Paracetamol, which is 151.16 g. And then we're going to multiply by avocados number 6.02, 2 times 10 to the 23rd molecules over one mole of paracetamol. So our milligrams of paracetamol are canceling out. Our grams of paracetamol are canceling out are moles of paracetamol are canceling out, leaving us with molecules And that equals 1.99 Times 10 to the 21st molecules of paracetamol. And that is our final answer. Thank you for watching. Bye.

Ch.3 - Molecules and Compounds

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Tro 5th Edition

Ch.3 - Molecules and Compounds

Problem 65a

Chapter 3, Problem 65a

How many molecules are in each sample? a. 6.5 g H₂O c. 22.1 g O₂ d. 19.3 g C₈H₁₀

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Determine the molar mass of water (H2O) by adding the atomic masses of hydrogen and oxygen: \(2 \times 1.01\, \text{g/mol} + 16.00\, \text{g/mol}\).

Calculate the number of moles of water in the sample using the formula: \(\text{moles} = \frac{\text{mass}}{\text{molar mass}}\).

Use Avogadro's number \(6.022 \times 10^{23}\, \text{molecules/mol}\) to convert moles of water to molecules.

Multiply the number of moles by Avogadro's number to find the total number of molecules.

Ensure all units are consistent and check calculations for accuracy.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). For water (H2O), the molar mass is approximately 18.02 g/mol, calculated by adding the atomic masses of its constituent elements: hydrogen (H) and oxygen (O). Understanding molar mass is essential for converting between grams and moles in chemical calculations.

Avogadro's Number

Avogadro's number, approximately 6.022 x 10^23, is the number of particles (atoms, molecules, etc.) in one mole of a substance. This constant allows chemists to relate the macroscopic scale of substances (grams) to the microscopic scale (molecules). It is crucial for determining how many molecules are present in a given mass of a substance.

Mole Concept

The mole concept is a fundamental principle in chemistry that provides a bridge between the atomic and macroscopic worlds. It allows chemists to count entities at the atomic scale by weighing them at the macroscopic scale. By using the mole, one can easily convert between the mass of a substance and the number of molecules it contains, facilitating various chemical calculations.

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How many molecules are in each sample? a. 6.5 g H2O c. 22.1 g O2 d. 19.3 g C8H10

Verified video answer for a similar problem:

Key Concepts

Molar Mass

Avogadro's Number

Mole Concept

How many molecules are in each sample? a. 6.5 g H₂O c. 22.1 g O₂ d. 19.3 g C₈H₁₀