Chem 11 Jan

Significant Figures

Digits in a measurement that indicate its precision. They include all known digits plus one estimated digit.

Accuracy

How close a measurement is to the accepted value.

Precision

How close a series of measurements are to each other.

Percent Error Formula

% = (experimental - literature) / literature * 100

Uncertainty in Measurement

A digit that indicates the range in which the accepted or true value most likely lies.

Direct Proportion

Relationship where as one variable increases, another variable increases.

Inverse Proportion

Relationship where as one variable increases, another variable decreases.

Empirical Formula

The simplest whole number ratio between atoms in a compound.

Molar Mass

The mass of 1 mole of a substance, expressed in grams per mole (g/mol).

Hydrates

Compounds containing water molecules integrated into their structure, often expressed with a specific ratio.

Ideal Gas Law

A formula that relates the pressure, volume, temperature, and amount of a gas, often expressed as PV=nRT.

Dissociation Reaction

When ionic compounds break up into ions when dissolved in water.

Endothermic Reaction

A reaction that absorbs energy, resulting in a drop in temperature of the substance.

Exothermic Reaction

A reaction that releases energy, resulting in a rise in temperature of the substance.

Chemical Change

A process where substances are transformed into new substances with different properties.

Physical Change

A change that does not alter the chemical composition of a substance.

Mixture

A combination of two or more pure substances that retain their individual properties.

Pure Substance

Material with a constant composition that consists of only one type of particle.

Colloid

A heterogeneous mixture with medium particle size that has a uniform composition.