PDF Notes: Lecture Set 4_annotated

What is molar mass?

It indicates the mass of one mole of a substance.

How is molar mass related to atomic mass?

They are numerically equal.

What does the atomic mass on the periodic table provide?

A conversion factor for moles per gram.

How do subscripts in a chemical formula function?

They serve as conversion factors for compound components.

What is percent composition?

It lists the mass percent of each element in a compound.

How is the percent composition of an element calculated?

By dividing the mass of the element by the molar mass of the compound.

What distinguishes a molecular formula from an empirical formula?

Molecular formulas show actual ratios, while empirical formulas show the smallest ratios.

What is the first step in calculating an empirical formula from mass data?

Find the masses of all elements present.

What happens if mole ratios are not close to whole numbers?

Multiply by a small whole number to obtain whole numbers.

What is the mass of 5.2 mol beryllium?

Calculate using the molar mass of beryllium.

How many moles are in 211 g of molybdenum?

Use the molar mass of molybdenum for conversion.

How many atoms of oxygen are in 0.347 mol Cl2O7?

Multiply the moles of Cl2O7 by the number of oxygen atoms.

What is the mass of 1 molecule of P4O10?

Calculate using the molar mass and Avogadro's number.

What mass of iron is combined with 11.7 g of oxygen in Fe3O4?

Determine using the molar mass of iron and oxygen.