Module 1: The Scientific Method & Exploring Bonds with Slime and Silly Putty

Vocabulary practice flashcards covering lab safety, bonding, polarity, micropipetting techniques, and the steps and variables of the scientific method.

Science

The systematic and logical approach to discovering how things in the universe work, as well as the body of knowledge accumulated through these discoveries.

Purpose of the Scientific Method

To help humanity reach valid and reliable answers for encountered problems based on the strongest available evidence and objective measures rather than opinion and belief.

Personal Protective Equipment (PPE)

Basic laboratory gear—including lab coats, gloves, and eye protection—that must be worn during all protocols to ensure laboratory safety.

Acid Dilution Safety Rule

The laboratory rule requiring concentrated acid to always be dripped slowly into water (never pouring water into concentrated acid) so reaction heat can dissipate safely.

Polarity

A chemical characteristic determined by molecular shape and electronegativity, existing when two covalently bonded atoms share valence electrons unequally.

Electronegativity

A relative property with no units that describes the attraction an atom has for electrons, which is highest in elements located on the upper right side of the periodic table like fluorine.

Pauling Scale

The most widely used scale for measuring and comparing the relative electronegativity values of chemical elements.

Carbon Dioxide ($\text{CO}_2$)

A compound containing two polar bonds between carbon and oxygen that has a linear molecular shape, causing the net electron pull to be zero and making the molecule nonpolar.

Water ($\text{H}_2\text{O}$)

A chemical compound with a bent shape and an unequal net pull of shared electrons, rendering the overall molecule polar.

Solvent

A substance, usually a liquid, that is capable of dissolving other chemical compounds.

Like-Dissolves-Like Principle

The chemical guideline stating that polar solvents dissolve polar molecules while non-polar solvents dissolve non-polar molecules.

Water Soluble Inks

Polar ink types that dissolve in polar solvents, such as those found in highlighters and Uni-ball point pens.

Water Insoluble Inks

Non-polar ink types that dissolve in non-polar solvents, such as newsprint, Sharpie markers, and most dry-erase markers.

Tare

To zero out the weight reading of a container (such as a weigh boat) on a digital scale prior to adding reagents.

Meniscus

The curved upper surface of a liquid column in container vessels such as graduated cylinders, measured from the bottom of the curve.

Micropipette

A precise laboratory tool used by scientists to accurately measure and deliver extremely small liquid volumes measured in microliters ($\mu\text{L}$).

Micropipette Volume Display

The set of vertically oriented windows on a micropipette showing numbers that indicate specific volume settings corresponding to the pipettor model size.

Micropipetting Technique

The correct operation protocol involving pushing the plunger to the first stop before fluid immersion to draw sample, maintaining vertical orientation, depressing to the second stop to expel liquid, and ejecting the tip.

Hypothesis

A tentative, testable, and falsifiable explanation for an observed natural phenomenon, commonly structured in an "if…, then…" statement.

Scientific Method Flowchart

A structured step-by-step procedure sequence: make an observation, ask a question, form a hypothesis, make a prediction, execute an experiment, analyze results, and report findings or revise hypothesis.

Control Group

The group in an experiment that receives baseline conditions identical to the experimental group except for the manipulation of the independent variable, establishing a basis for comparison.

Experimental Group

The group in an experiment that receives the specific manipulation of the independent variable being tested.

Independent Variable

The factor or condition in an experiment intentionally manipulated by the researcher to determine its effect on an outcome.

Dependent Variable

The outcome factor measured in an experiment that changes as a direct result of the investigator's manipulation of the independent variable.

Confounding Variables

Uncontrolled external factors or variables that must be tightly managed across experimental and control groups to ensure measurable differences are solely caused by the independent variable.

Beriberi Experiment (Gallus domesticus)

Dr. Eijkman's study demonstrating that chickens (Gallus domesticus) fed polished white rice developed beriberi due to a lack of thiamine, disproving the original hypothesis of a bacterial infection.

Zone of Inhibited Growth (Penicillium)

A clear area surrounding a colony of Penicillium mold on an agar culture plate where Staphylococcus bacteria are killed and prevented from growing.

in order pre-lab write up

1. Title

2. date

3. purpose/objectives

4. materials

5. Procedure

6. Data tables

Polarity of a molecule is based on two primary factors:

Shape and Electronegativity

why does equally pulling bonds account for CO2’s nonpolar nature

because its two identical oxygen atoms pull electrons in exact opposite directions with equal strength, completely canceling each other out.

Arrange each step in the scientific method in the proper order:

1. Ask a question

2. Background research

3. Construct a hypothesis

4. Procedure

5. Test with an experiment

6. Analysis of Data/Draw Conclusions

7. Communicate Results

Describe the appropriate way to hold a micropipette with a tip full of liquid. Explain why it is so important to hold the micropipette in the way you described:

Hold the micropipette vertically (straight up and down) at all times whenever there's liquid in the tip. This matters because tilting it lets the liquid run into the body of the pipette instead of staying in the tip — this can contaminate the pipette internally, throw off your measurement accuracy, and potentially damage the instrument.

your own words, name the five overall learning objectives for BISC 1111 Laboratory as stated in the lab syllabus:

1. Build hands-on lab skills to better understand cell and molecular biology

2. Learn to design, run, and analyze real scientific experiments

3. Improve scientific writing ability

4. Strengthen critical thinking and analytical skills

5. Deepen understanding of the core concepts covered in lecture

In your own words, describe the purpose of a lab notebook in 1-2 well reasoned sentences:

A lab notebook is where you record your procedures, observations, and data in real time, creating an accurate, permanent record of exactly what you did and what happened during an experiment. This matters because science depends on reproducibility — a good notebook lets you (or someone else) retrace your steps, catch errors, and trust your results later on.

Explain the difference between causation and correlation:

Correlation is the relationship between the two variables

just means two variables tend to change together (when one goes up, the other tends to go up or down too) but that doesn't tell you why.

Causation - A is the direct factor of B happening

• means one variable directly causes the change in the other. Correlation without a controlled experiment can't prove causation, because a third, hidden variable might actually be driving both things you're observing.