Lecture Jan27th-29th Organic Chem

Potential Energy

Energy that is stored in an object by virtue of its position.

Kinetic Energy

Energy an object possesses by virtue of its motion.

Solid

Matter that has a definite shape and volume, commonly existing in crystalline form.

Liquid

Matter that has a definite volume but no fixed shape, taking the shape of its container.

Gas

Matter that has no fixed shape or volume and evenly spreads out to fill its container.

Plasma

A form of matter composed of electrically charged atomic particles, primarily found in outer space.

Physical Property

A property that can be observed or measured without changing the chemical composition of the substance.

Chemical Property

The ability of a substance to react or change to form a new substance with different properties.

Pure Substance

Matter with a fixed composition that cannot be separated into other forms by physical change.

Mixture

A combination of two or more pure substances where the composition can vary and can be separated by physical change.

Homogeneous Mixture

A uniform blend of two or more substances where every part is exactly like the other part.

Heterogeneous Mixture

A mixture where different parts have different properties, and components retain their individual properties.

Element

A pure substance that cannot be broken down into simpler substances, serving as the basic building blocks of matter.

Metal

Elements that have luster, conduct electricity and heat, and are malleable.

Non-Metal

Elements that lack luster and do not conduct heat and electricity.

Metalloid

Elements that possess properties of both metals and non-metals.

Noble Gases

Inert elements that are non-reactive.

Atom

The smallest individual particle of an element.

Compound

A pure substance made of two or more elements that are chemically combined.

Ionic Compound

Compounds formed through oppositely charged ions.

Molecular Compound

Compounds formed through molecular bonds between elements.

Atomic Mass

A measurement assigned to atoms based on the mass of hydrogen as a reference.

Molecular Mass

The mass of a molecular compound.

Formula Mass

The mass of an ionic compound.

Gram Atomic Mass

The atomic mass of an element expressed in grams.

Mole

A unit representing 6.02 x 10^23 particles, atoms, or molecules, equal to the gram atomic mass.

Avogadro's Number

The number of particles in one mole of a substance, approximately 6.02 x 10^23.

Crookes Cathode Ray Tube

An early experimental apparatus that contributed to the discovery of the electron.

Plum Pudding Model

J.J. Thompson's model of the atom, depicting it as a mixture of positively charged 'pudding' with negatively charged 'corpuscles'.

Proton

A positively charged subatomic particle located in the nucleus of an atom.

Neutron

A neutral subatomic particle located in the nucleus of an atom.

Electron

A negatively charged subatomic particle that orbits the nucleus of an atom.

Democritus

Ancient philosopher who proposed that atoms are the smallest particles of matter.

John Dalton

Scientist who formulated Dalton's Atomic Theory, asserting that all matter is made up of atoms.

Ernest Rutherford

Scientist who discovered the nucleus of the atom through his experiments.

James Chadwick

Scientist who confirmed the existence of the neutron in 1932.

Subatomic Particle

Particles that make up an atom: protons, neutrons, and electrons.

Chemical Change

A change in a substance that results in a new substance with different chemical composition.

Physical Change

A change that affects one or more physical properties without altering the chemical composition.

Crystalline Solid

A solid that has a definite, fixed internal structure.

Amorphous Solid

A solid that does not have a fixed internal structure or form.

Phase

Any part of a system with uniform composition and properties.

Solution

A homogeneous mixture where one substance is dissolved in another.

Atomic Number

The number of protons in an atom's nucleus, which determines the element.

Atomic Weight

The weighted average of the masses of an element's isotopes.

Chemical Formula

A notation that represents the elements in a compound and their ratios.

Molecular Formula

A chemical formula that shows the actual number of atoms in a molecule.

Empirical Formula

A chemical formula that represents the simplest whole-number ratio of atoms in a compound.

Boiling Point

The temperature at which a liquid becomes a gas.

Melting Point

The temperature at which a solid becomes a liquid.

Density

The mass of a substance per unit volume.

Solubility

The ability of a substance to dissolve in a solvent.

Concentration

The amount of a substance in a given volume of solution.

What is the difference between a physical change and a chemical change?

A physical change affects one or more physical properties without altering the chemical composition, while a chemical change results in a new substance with a different chemical composition.

What is a mole in chemistry?

A mole is a unit representing 6.02 x 10^23 particles, atoms, or molecules, equivalent to the gram atomic mass.

What does gram mass refer to?

Gram mass typically refers to the atomic mass of an element expressed in grams.

Why is the mole concept important in chemistry?

The mole concept is important because it allows chemists to count particles by weighing them, facilitating stoichiometric calculations.

How do you calculate the mass of a substance from moles?

To calculate the mass of a substance from moles, multiply the number of moles by the molar mass of the substance.

What is molar mass?

Molar mass is the mass of one mole of a substance, usually expressed in grams per mole (g/mol).