Skip to main content
Ch.2 - Atoms & Elements
Tro - Chemistry: A Molecular Approach 5th Edition
Tro5th EditionChemistry: A Molecular ApproachISBN: 9780134874371Non è quello che usi tu?Cambia libro di testo
Capitolo 2, Problema 88

Calculate the number of atoms in each sample. a. 14.955 g Cr

Guida verificata passo dopo passo
1
Identify the molar mass of chromium (Cr) from the periodic table, which is approximately 51.9961 g/mol.
Use the formula to convert grams to moles: \( \text{moles of Cr} = \frac{\text{mass of Cr in grams}}{\text{molar mass of Cr}} \).
Substitute the given mass of chromium (14.955 g) and its molar mass into the formula to find the moles of Cr.
Use Avogadro's number, \( 6.022 \times 10^{23} \text{ atoms/mol} \), to convert moles of Cr to atoms: \( \text{atoms of Cr} = \text{moles of Cr} \times 6.022 \times 10^{23} \text{ atoms/mol} \).
Perform the multiplication to find the total number of atoms in the sample.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
2m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). For chromium (Cr), the molar mass is approximately 51.996 g/mol. This value is essential for converting grams of a substance to moles, which is a necessary step in determining the number of atoms in a sample.
Video consigliato:
Percorso guidato
02:11
Molar Mass Concept

Avogadro's Number

Avogadro's number, approximately 6.022 x 10²³, 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 (individual atoms or molecules). It is crucial for calculating the total number of atoms in a given mass of an element.
Video consigliato:

Conversion from Grams to Atoms

To find the number of atoms in a sample, one must first convert the mass of the sample to moles using the molar mass, and then multiply the number of moles by Avogadro's number. This two-step conversion is fundamental in stoichiometry, allowing for the quantification of particles in a chemical context.
Video consigliato:
Percorso guidato
03:45
Weight Conversion Example