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2. Atoms & Elements

Mole Concept

2. Atoms & Elements

Mole Concept

Open Question
For an atom to achieve maximum stability and become chemically inert, what must occur?
Multiple Choice
How many carbon atoms are present in one mole of 12C?
Multiple Choice
A sample contains 351 kg of calcium (Ca). How many moles of calcium are present in the sample? (Molar mass of Ca = 40.08 g/mol)
Open Question
Calculate the mass of 1.00×10²⁴ (a septillion) molecules of water.
Open Question
How many molecules of N₂O₄ are in 76.3 g N₂O₄? The molar mass of N₂O₄ is 92.02 g/mol.
Multiple Choice
How many moles of atoms are present in 4.00 g of 13C?
Open Question
How many moles of propylene (C₃H₆) are in 25.0 g?
Multiple Choice
A cup of water contains 13.9 moles of water. How many molecules of water are in the cup?
Multiple Choice
How many moles are present in 168 g of KOH?
Multiple Choice
Which of the following best represents the number of particles (atoms, molecules, or ions) present in one mole of a substance?
Multiple Choice
How many atoms of chlorine are present in 1.00 mol of chlorine gas (Cl_2)?
Multiple Choice
How many moles are present in 15.0 g of AsH_3 (arsine)? (Molar mass of AsH_3 = 77.95 g/mol)
Multiple Choice
How many atoms are present in 1.50 moles of Hg?
Multiple Choice
How many moles of H_2O are present in 360 grams of water?
Multiple Choice
Which quantity is equal to one mole of gold, $A u$ ?