Official Santa Fe College CHM1030 Lab Final Dr. Weaver

true

True or false? All non-zero digits (1-9) are always significant.

3 sig figs

How many sig figs does 456 have?

false, any zeros between non-zero digits are significant.

True or false? Zeros between non-zero digits are not significant.

3 sig figs

How many sig figs are in 405?

true

True or false? Trailing zeros are NOT significant unless specified by a decimal point or written in scientific notation.

2 sig figs; 4 sig figs; 4 sig figs

1500 → ?; 1500. → ?; 1.500 × 10³ → ?

true

True or false? Leading zeros are NEVER significant.

2 sig figs

How many sig figs are in 0.0025?

false, they are significant

True or false? Trailing zeros in a number with a decimal point ARE NOT significant.

3; 3

2.50 → ?; 0.0400 → ?

1 Scientific Method - Ask a Question

State the step in the scientific method: Something like: 'Why does one liquid fizz faster than another?'

2 Scientific Method - Make a Hypothesis

State the step in the scientific method: A guess you can test: 'If I shake the red bottle, it will fizz faster than the blue one because it has more sugar.'

3 Scientific Method - Do an Experiment

State the step in the scientific method: Set up your test! Use tools to measure (like time, volume, temperature).

4 Scientific Method - Collect Data

State the step in the scientific method: Write down your observations and numbers. Example: Red bottle fizzed in 4 seconds. Blue took 6 seconds.

5 Scientific Method - Analyze the Data

State the step in the scientific method: Look for patterns. Which one fizzed faster? Do your numbers support your guess?

6 Scientific Method - Make a Conclusion

State the step in the scientific method: Say what your experiment showed. 'The red bottle did fizz faster, so my hypothesis was correct.'

7 Scientific Method - Share or Repeat

State the step in the scientific method: Tell someone or do it again to double-check!

Example of Scientific Method

Question: Does hot water dissolve sugar faster than cold? Hypothesis: Hot water will dissolve sugar faster. Experiment: Add sugar to both hot and cold water. Data: Hot = 10 sec, Cold = 35 sec. Conclusion: Hot water dissolves sugar faster — hypothesis supported!

chemical equation

Reactants → Products.

H₂ + O₂ → H₂O.

State an example of a chemical equation.

Sodium = Na; Water = H₂O; Carbon dioxide = CO₂; Magnesium chloride = MgCl₂.

What are some examples of chemical formulas?

(s) = solid; (l) = liquid; (g) = gas; (aq) = aqueous (dissolved in water).

What are the 4 states of matter you will see in chemical equations?

NaCl (aq) + AgNO₃ (aq) → AgCl (s) + NaNO₃ (aq).

State an example of a chemical equation with states included.

The number of each atom must be equal on both sides.

How do you know a chemical equation is balanced?

Don't change subscripts; only change coefficients.

Tip for balancing equations?

2H₂ (g) + O₂ (g) → 2H₂O (l).

What's an example of balancing an equation?

Electron configuration

A representation of the arrangement of electrons in an atom.

Bohr model

A model of the atom that depicts electrons in circular orbits around the nucleus.

Ions

Charged particles like Na⁺ or Cl⁻ where the symbol tells you the base element.

Zinc

If it fizzes with acid and disappears, it's likely ...

Magnesium

If it fizzes with acid and disappears, it's likely ...

Copper

If it stays the same and doesn't react, it might be ...

Lab Safety Rule

Always wear goggles and apron to protect your eyes and clothes from splashes.

Lab Safety Rule

No food or drinks in the lab to avoid contamination.

Lab Safety Rule

Tie back long hair to prevent fire hazards.

Lab Safety Rule

Know where safety gear is located before starting.

Lab Safety Rule

Label all chemicals to avoid confusion.

Lab Safety Rule

Handle glassware and equipment carefully to avoid accidents.

Lab Safety Rule

Dispose of waste properly according to instructions.

Lab Safety Rule

Clean up your station after use to maintain a safe environment.

Lab Safety Rule

Report all spills or accidents immediately.

Read every digit you can see.

How do you record a measurement?

When you estimate one more digit past what's marked on the measurement tool.

What's an uncertain digit?

Example of Uncertainty

If a beaker shows 45 mL and you estimate it's just past that, record 45.2 mL.

% Copper = (0.15 / 1.00) × 100 = 15%

How do you find the percent composition of copper?

Single replacement reaction

A reaction where one element replaces another in a compound.

Reactivity series

A list that ranks elements by their ability to displace others in reactions.

Yellow/Orange

Na+ Flame Color

Violet/Purple

K+ Flame Color

Orange

Ca2+ Flame Color

Yellow/Gold

Fe3+ Flame Color

Green

Cu2+ Flame Color

None

Mg2+ Flame Color

Bright White

Mg(s) Flame Color

Red

Li+ Flame Color

Bunsen burner

Ring stand

Pipestem triangle

Evaporating dish

Mortar and pestle

Utility clamp

Gas bottle

Iron ring

Crucible and cover

Test tubes

Beaker

Wire gauze

Safety goggles

Corks

Watch glass

Assorted rubber stoppers

Erlenmeyer flask

Lab burner

Tongs

Pipet

Thermometer

Buret

Graduated cylinder

Wash bottle

Micropipets

Spatula

Scoopula

24-well plate

Funnel

Test tube

Wire brush

Test tube holder

Dropper

File

Forceps

Lab equipment which produces a single open gas flame, which is used for heating, sterilization, and combustion

Bunsen burner function

Device used to evaporate solids and supersaturated liquids

Evaporating dish function

Probably the most common vessel for holding liquids in the lab

Beaker function

Used in many lab activities as the support for another apparatus

Iron ring function

tool used to crush, grind, and mix solid substances

Mortar and pestle

Must be worn for lab activities to protect the eyes.

Safety goggles function

used in chemistry as a surface to evaporate a liquid, to hold solids while being weighed, or as a cover for a beaker

Watch glass function

Used to contain liquids in test tubes and flasks

Rubber stoppers & Corks function

A squeeze bottle with a nozzle, used to rinse various pieces of laboratory glassware, such as test tubes and round bottom flasks

Wash Bottle function

A pipette (also called a pipet, pipettor or chemical dropper) is a laboratory instrument used to transport a measured volume of liquid

Pipets, Micropipets & Droppers function