Multiple Choice
When 2.50 mol of Al and 3.00 mol of Cl2 combine in the reaction 2Al(s) + 3Cl2(g) ⇌ 2AlCl3(s), how many moles of AlCl3 are formed?
3. Chemical Reactions
Stoichiometry
Struggling with General Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Calculate the mass of 4.50 × 1025 O3 molecules.
A
74.7 g
B
1.20 × 103 g
C
3.59 × 103 g
D
224 g
Verified step by step guidance1
Determine the molar mass of O3 (ozone) by adding the atomic masses of three oxygen atoms. The atomic mass of oxygen is approximately 16.00 g/mol, so the molar mass of O3 is 3 × 16.00 g/mol.
Use Avogadro's number, which is 6.022 × 10^23 molecules/mol, to convert the number of O3 molecules to moles. Set up the conversion factor as (1 mole/6.022 × 10^23 molecules).
Calculate the number of moles of O3 by dividing the given number of molecules (4.50 × 10^25) by Avogadro's number.
Multiply the number of moles of O3 by the molar mass of O3 to find the mass in grams. Use the formula: mass (g) = moles × molar mass (g/mol).
Ensure that the units cancel appropriately during the calculations, leaving you with the mass in grams as the final unit.
Related Videos
Related Practice
