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2. Atoms & Elements

Mole Concept

2. Atoms & Elements

Mole Concept

Multiple Choice
How many moles of Cl are present in one mole of CaCl2?
Multiple Choice
A 3.00 mole sample of K_2S contains how many atoms of potassium?
Multiple Choice
How many atoms are present in 179.0 g of iridium (Ir)? (Atomic mass of Ir = 192.2 g/mol)
Multiple Choice
How many phosphorus atoms are present in 158 kg of elemental phosphorus (P)?
Multiple Choice
Which of the following tasks most likely involves a calculation that uses moles?
Multiple Choice
How many atoms are present in a 12.0 g sample of lithium (Li)? (Atomic mass of Li = 6.94 g/mol)
Open Question
What is the mass of 1.7 × 10²³ atoms of zinc (Zn)?
Open Question
Number of o atoms in 6.25×10⁻³ mol Al(NO₃)₃
Multiple Choice
What is the mass in grams of one mole of any pure substance called?
Multiple Choice
A sample contains 1.25 grams of CH_4 and no other substances. What is the mole fraction of O_2 in this sample?
Open Question
Determine the number of moles of oxygen atoms in each of the following.
Multiple Choice
How many argon (Ar) atoms are present in 1.5 × 10^2 g of argon?
Multiple Choice
A copper sample has a mass of 63.5 g. How many moles of copper are present in the sample? (Atomic mass of Cu = 63.5 g/mol)
Multiple Choice
A solution has a concentration of 0.025 M HCl. How many moles of H+ are present per liter in this solution? (Use the decimal form of your answer.)
Open Question
How many atoms are in a sample of 2.39 moles of neon (Ne) atoms?