Sig Figs
3
One mole contains this many particles
6.02 × 10²³ particles
The molar mass of NaCl is this value
58.44 g/mol
When adding or subtracting measured values, your final answer is rounded according to this rule.
Fewest decimal places
This SI base unit measures the amount of substance
mole, mol
In Al₂(NO₃)₃, there are this many Al atoms, N atoms, and O atoms in one formula unit
2 Al, 3 N, and 9 O.
This many significant figures are in 20.040
5
Calculate the number of atoms in 2.50 mol Si
1.51 × 10²⁴ Si atoms
Determine the number of moles in 18.0 g H₂O
0.999 mol H₂O
Calculate and round correctly: 100.0 mL − 26.84 mL
73.2 mL
Calculate the number of atoms in 0.250 mol Cu
1.51 × 10²³ Cu atoms
What is the mass of 0.500 mol Fe?
27.9 g Fe
Calculate using the correct number of significant figures: 3.10 mol × (6.022 × 10²³ atoms/mol).
1.87 × 10²⁴ atoms
6.00 g H₂O₂ is approximately 0.176 mol. This is approximately how many molecules.
1.06 × 10²³ molecules
A sample contains 3.01 × 10²³ molecules of CO₂. What is the mass of the sample in grams?
22.0 g CO₂