While Participating in a Timed Experiment, the Participants in the Experimental

question 32

Multiple Choice

While participating in a timed experiment, the participants in the experimental group had to leave the room because of a fire drill. Which potential threat to internal validity would this example illustrate according to Campbell and his colleagues?

• A) maturation
• B) selection
• C) instrumentation
• D) history

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Definitions:

Harmful

Referring to anything that can cause damage or adverse effects on living organisms or the environment.

Nonpolar Covalent

A type of chemical bond where two atoms share a pair of electrons with each other equally because they have similar electronegativities.

Polar Covalent

A polar covalent bond is a type of chemical bond where a pair of electrons is unequally shared between two atoms, leading to a molecule with partial positive and negative charges.

Hydrogen

A chemical element with symbol H and atomic number 1, being the lightest and most abundant element in the universe.