Unit 1 & Chapter 2: Scientific Method and Chemistry of Life

Fill-in-the-blank practice flashcards covering scientific inquiry, experimental design, subatomic particles, chemical bonding, and properties of water.

A hypothesis is a prediction or explanation that can be tested by an __________ .

experiment

In a controlled experiment, the variable that is manipulated by the researcher is called the __________ variable.

independent

The standard to which comparisons are made in a controlled experiment is known as the __________ group.

control

Data that is measured or counted and consists of numerical values is classified as __________ data.

quantitative

The most common type of bias in data interpretation where people tend to see what they already agree with is __________ bias.

confirmation

A scientific theory is supported by a wide range of scientific __________ and can change based on new evidence.

evidence

In a carbon atom, positively charged protons and uncharged neutrons reside in the __________ .

nucleus

The atomic number of an element is determined by its total number of __________ .

protons

According to the octet rule, the outer orbitals of an atom generally hold up to $8$ __________ .

electrons

Oxygen is the most abundant element in the human body, accounting for $65\%$ of its __________ composition.

elemental

An ionic bond is formed when one or more electrons are __________ from one atom to another.

transferred

A covalent bond is formed when electrons are __________ between atoms.

shared

Water is a polar molecule, allowing a hydrogen bond to form between its slightly positive hydrogen atom and an atom with a partial __________ charge.

negative

Water has a high __________ heat due to its hydrogen bonds, requiring a large amount of energy to change its temperature.

specific

Ice floats on liquid water because its hydrogen bonds are more stable, making ice __________ dense than liquid water.

less

In a solution, the substance that does the dissolving is called the __________ .

solvent

Acids release hydrogen ions ($H^+$) in solution, resulting in a pH value lower than $7$, whereas bases produce __________ ions ($OH^-$).

hydroxide

Each number on the pH scale represents a $10$-fold change in the concentration of __________ ions.

hydrogen

Grapefruit juice is $1,000$ times more acidic than human __________ .

urine

In the marsh grass experiment, researchers added nitrogen fertilizer as the independent variable and measured the growth of marsh grass as the __________ variable.

dependent