Moles Unit test

moles → liters amount

22.4L

moles → rp amount

6.02×10²³

moles → mass amount

atomic weight

% by mass

% by mass = (part/whole) x 100%

calibration curve formula

242.09 x density - 241.5

Density

g/ml

% error

((experimental value/ actual value) / actual value) x 100%

Empirical formula

Lowest ratio of atoms

Molecular formula

Actual number of atoms

Steps to find empirical formula

1. convert to moles

2. divide by lowest #

3. multiply to a whole number

Steps to molecular formula

1. find molar mass

2. divide actual mass by compound mass

3. multiply formula by number found in step 2

Molarity

molarity (M) = moles/liters

Sig Figs

• Non-zero digits:

  All non-zero digits are significant

• Zeros between non-zero digits:

  Zeros that are between two non-zero digits are significant

• Leading zeros:

  Zeros that come before the first non-zero digit are never significant

• Trailing zeros:

  • With a decimal point: Trailing zeros are significant if they are to the right of the decimal point

  • Without a decimal point: Trailing zeros in a whole number without a decimal are not significant

• Scientific notation:

  For numbers in scientific notation (

  N×10xcap N cross 10 to the x-th power

  𝑁×10𝑥

  ), all digits in the coefficient (

  Ncap N

  𝑁

  ) are significant.