Chemistry 4thQ

Phases of Matter

Different states of matter include solid, liquid, gas, plasma, Bose-Einstein condensate, quark-gluon plasma, and degenerate matter.

Phase Changes

Processes like melting, freezing, evaporation, condensation, sublimation, and deposition involve transitions between different states of matter.

Specific Latent Heat (SLH)

The energy required to change the state of 1kg of a substance without a change in temperature.

Particulate Nature of Matter

Matter is composed of particles like atoms, molecules, and ions, each with specific properties and behaviors.

Distinguishing Properties

Solids have fixed shape & volume, liquids take the shape of the container, and gases have no fixed shape or volume.

Atomic Structure

Atoms consist of protons and neutrons in the nucleus, with electrons orbiting around it.

Ions

Atoms with a charge due to the loss or gain of electrons, forming cations (positive) or anions (negative).

Quantum Mechanical Model

Describes the behavior of electrons in atoms, including principles like Aufbau, Hund's rule, and Pauli exclusion.

Electron Configuration

Represents the arrangement of electrons in shells and subshells based on quantum numbers and energy levels.

Periodic Table of Elements

Dmitri Mendeleev introduced the periodic table, organizing elements by atomic number and properties in periods and groups.

Boron Group

• earth metals

• can carry a charge of 4

• 4 valence electrons

Oxygen Group

• aka Chalcogens

• diverse properties, intermediate between metals & nonmetals

• 6 valence electrons

Carbon Group

• aka Tetrels

• can carry a charge of 4

• diverse properties, intermediate between metals & nonmetals

• 4 valence electrons

Nitrogen Group

• aka Pnictogens 

• diverse properties, intermediate between metals & nonmetals

• 5 valence electrons

Noble Gases

• aka Inert Gases

• extremely unreactive

• 8 valence electrons = stable

Halogens

• reactive nonmetals

• melting & boiling points increase with increasing atomic #

• changes state as it moves down

• high electron affinities

• 7 valence electrons

• may include Hydrogen

Atomic Size/Radius

• measured as one-half the distance between the nuclei of identical atoms that are bonded together

• increases from right to left

• increases from top to bottom

Ionization energy

• energy required to remove an electron from a gaseous atom to form a cation

• increases from left to right

• increases from bottom to top

Electron Affinity

• ability of an atom to accept an electron

• metals usually have low electron affinity, while nonmetals have high electron affinity.

• increases from left to right

• increases from bottom to top

Electronegativity

• ability of an atom to attract electrons towards itself.

• when atoms of two different elements share a pair of electrons, one atom becomes partially positive and the other becomes partially negative.

• increases from left to right

• increases from bottom to top

What is the formula for:

A vendor has 200 grams of a substance at 0°C. How much energy is needed to completely change its phase? (Specific latent heat is 210 J/g)

E = mL

What is the formula for:

If 3 kg of a substance at 100°C releases 6,780,000 J of energy, what is the specific latent heat of the substance?

L = E/m

formula for:

A scientist changes the phase of 1 kg of a substance at 100°C, releasing 2,260,000 J of energy. What is the specific latent heat?

L = E/m

How much mass of a substance can be melted by supplying 52,500 J of energy at its melting point? (Specific latent heat is 105 J/g)

m = E/L