4.1 The mole

Question 1

What are collective numbers

Answer 1

Collective numbers are units collecting objects into groups of a specific size ex dozens, reams (500 pages of paper)

Question 2

What collective number is unit 4 about

Answer 2

Moles are a collective number frequently used in chemistry, it is used while counting molecules, ions and other small particles

Question 3

What is 1 mole

Answer 3

One mole is the number of atoms in 12 grams of carbon 12, around 6.02 x 10^23 atoms

Question 4

What number is important for moles

Answer 4

The number of atoms in a mole (6.02 x 10^23 atoms) is know as Avogadro’s Number (NvA) , in honour of Amadeo Avogadro (1776-1856). Though he did not come up with this number

Question 5

What are the guidelines for Correctly Doing Chemistry Conversion Calculations

Answer 5

1. Start a calculation with the number having the simplest units wherever possible.
2. “When in doubt, convert to mols…” If you don’t know what to do first then convert to mols and go from there.
3. Always include units and chemical species when you write a number.
4. Do not use slash “/” signs in a calculation. They are fine in your final answer, but not in a calculation.
5. The horizontal line in a conversion factor, means “for every”. Saying “for every” in your head as you read your calculation should help you know where to place units.
6. Show your cancellation of units.
7. It is always better to do a calculation in one process.
8. Only round to final sig figs in the final answer. If you must break a calculation into parts, be sure to keep at least one extra sig fig.

Question 6

What is a formula unit

Answer 6

Formula Unit- Ionic compounds actually form large lattices rather than individual molecules. Therefore you may see the termformula unitsused in place of molecules. You can think of a formula unit as the equivalent of a molecule.

Question 7

What are particles

Answer 7

Particles- This word may refer to either atoms or molecules. It depends on the context in which it is given.

Question 8

What is At

Answer 8

At- You may seeAtused as an abbreviation foratoms

Question 9

What are Mlcs or Molecs

Answer 9

Mlcs or Molecs- You may see either of these used as an abbreviation formolecules.
DoNOT usemorMas an abbreviation for either molecules or mols asmstands formeterandMstands forMolaritywhich you will learn more about later.

Question 10

If you need the number of a specific atom from a mole of a compound what do you do

Answer 10

Sometimes you need to determine the number of atoms in a molecule or the number of a specific atom in a molecule after converting moles to actually numbers. do this by a conversion factor of made by number of atoms per molecule