Molar Mass; Converting mass to atoms and viceversa

Molar Mass; Converting mass to atoms and viceversa

By Santiago Perez

Multiple Choice

What is a mol?

• The mole (symbol: mol) is the base unit of amount of substance ("number of substance") in the International System of Units or System International (SI), defined as exactly 6.02214076×10^23 particles

• The mole (symbol: mol) is the base unit of amount of substance ("number of substance") in the International System of Units or System International (SI), defined as exactly 6.02214076×10^23 atoms

• The mole (symbol: mol) is the base unit of amount of substance ("number of substance") in the International System of Units or System International (SI), defined as exactly 6.02214076×10^23 ions

• The mole (symbol: mol) is the base unit of amount of substance ("number of substance") in the International System of Units or System International (SI), defined as exactly 6.02214076×10^23 electrons

We can use Avogadro's number as a conversion factor, or ratio, in dimensional analysis problems.

 

If we are given the number of atoms of an element X, we can convert it into moles by using the relationship

 

                1 mol X=6.022×10^23 X atoms.

Converting Between Number of Atoms to Moles and Vice Versa

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Draw

The element carbon exists in two primary forms: graphite and diamond. How many moles of carbon atoms is 4.72×10^24 atoms of carbon?

your task: Write (or draw) a proportion that you would used to solve this problem. DO NOT SOLVE IT YET

​Molar mass is defined as the mass of one mole of representative particles of a substance.

By looking at a periodic table, we can conclude that the molar mass of the element lithium is 6.94g, the molar mass of zinc is 65.38g, and the molar mass of gold is 196.97g.​

• Each of these quantities contains 6.022×10^23 atoms of that particular element.

• The units for molar mass are grams per mole or g/mol.

• 1.00 mol of carbon-12 atoms has a mass of 12.0g and contains 6.022×10^23 atoms.

• 1.00 mole of any element has a mass numerically equal to its atomic mass in grams and contains 6.022×10^23 particles.

The mass, in grams, of 1 mole of particles of a substance is now

​Converting Grams to Moles of an Element and Vice Versa

We can also convert back and forth between grams of an element and moles. The conversion factor for this is the molar mass of the substance. The molar mass is the ratio giving the number of grams for each one mole of the substance. This ratio is easily found by referring to the atomic mass of the element using the periodic table. This ratio has units of grams per mole or g/mol.

Draw

Chromium metal is used for decorative electroplating of car bumpers and other surfaces. Find the mass of 0.560 moles of chromium. Your Task: 1. Indicate what is the information given 2. write what is your first step in solving this problem 3. do the first step 4. Prepare a concept map, (this is a diagram explaning what your about to do) 5. Write the proportion that would solve this problem, DO NOT SOLVE IT YET.