Chemical Bonds and Reactions Flashcards

Flashcards covering chemical bonds, reactions, and quantitative aspects of chemical reactions.

What is a Covalent Bond?

The sharing of at least one pair of electrons by two non-metals.

What is an Ionic Bond?

Involves a complete transfer of electron(s). Metal forms cation. Non-metal forms anion.

What is a Metallic Bond?

Between two metals. Metal atoms very closely packed, valance shells overlap. Valence electrons are able to move between atoms. Known as delocalized electrons or free electrons

What are Diatomic Molecules?

Molecules composed only of two atoms of the same element.

What is a Polar Covalent Bond?

Electrons shared unequally between atoms due to difference in electronegativity.

What is a Nonpolar Covalent Bond?

Electrons shared equally between atoms due to similar or identical electronegativity.

What is Atomic Radius?

The average distance from the center of the nucleus to the border of the outer orbital.

What is Electron Affinity?

The amount of energy released when an electron is added to a neutral atom to form and anion. Is a description of how likely an atom is to accept an electron.

What is Electronegativity?

The tendency of an atom in a molecule to attract the shared pair of electrons towards itself.

What is Ionization Energy?

The minimum energy required (per mole) to remove an electron from an atom, in gaseous phase.

What are Valence Electrons?

The outermost electrons of an atom that participate in chemical interactions and determine the chemical properties of the element.

What is the Octet Rule?

Atoms are most stable when their valence shells are filled with eight electrons.

What are Lewis Dot Diagrams?

Used to show the position of the valence electrons around an element.

What is a Chemical Formula?

A way to represent the composition of a substance by showing the elements present and the number of atoms of each element in a molecule or formula unit.

What are Physical Changes?

Usually easy to reverse, no new substances formed, small energy changes involved.

What are Chemical Changes?

Usually hard to reverse, new substances formed, large energy changes involved.

What is the Law of Constant Composition?

In any particular chemical compound, all samples of that compound will be made up of the same elements in the same proportion or ratio as per its chemical formula.

What is the Law of Conservation of Matter?

In a chemical reaction, the sum of the mass of the reactants equals the sum of the mass of the products.

What are Ion Exchange Reactions?

Where the cations exchange their respective anions.

What are Precipitation Reactions?

Anions and cations bond with new partners to form insoluble salts.

What are Acid-Base Reactions?

Take place between acids and bases. Through the exchange of ions, the products formed will be water and an ionic salt.

What are Gas Forming Reactions?

Anions and cations have bonded with new partners and through the exchange of ions a gas is formed.

What are Redox Reactions?

Occur when one reactant gains electron(s) called reduction, and another reactant loses electron(s) called oxidation.

What is a Mole?

The name for a special number of particles, 6.02 x 10^23.

What is Molar Mass (M)?

The mass of one mole of particles (atoms, molecules or formula units) and is measured in the unit g.mol-1.

What is Relative Atomic Mass (Ar)?

The average mass of an atom compared to the mass of a Carbon 12 atom. It is measured in atomic mass units (amu).

What is Percentage Composition?

The mass of each atom present in the compound expressed as a percentage of the total mass of the compound.

What is Molecular Formula?

Actual number of each atom.

What is Empirical Formula?

Simplest whole number ratio of the atoms.

What are Solutions?

Homogeneous (uniform) mixtures of two or more substances.

What is Concentration of a Solution?

The number of moles of solute per unit volume of solution.

What is Avogadro’s Law?

One mole of any gas occupies the same volume at the same temperature and pressure. VM for all gases at STP is 22.4 dm3.mol-1

What is Empirical Formula?

The chemical formula of a compound that shows the smallest whole number ratio of the atoms.