A metallic solid is made of many metal atoms composed of kernels and electrons, the positive kernels held in arrays while the negative electrons float around them, at the same time, attracted to each other due to their opposite electrostatic nature and engaged in bonding known as the metallic bond.
The regular, periodic arrangement of atoms, ions or molecules at the lattice points of a crystal in a three-dimensional space is called the space lattice or the crystal lattice.
The activation energy (Ea) is the minimum amount of extra energy absorbed by the reactant molecules from an energy source such as heat, light, etc., to attain the threshold value for effective collisions to occur and thereby to form an intermediate complex (active state) that finally results in product formation.
| Qualitative Analysis | Quantitative analysis |
|---|---|---|
Aim | Identifies what compounds or functional groups are present. Therefore, the type of information obtained is descriptive. For example, whether the compound changed color, evolved gas, or formed a precipitate.
| Measures how much of a compound is present and, therefore, numerically describes its quantity. |
| Reactant | Reagent | Catalyst |
|---|---|---|---|
Definition | A substance that participates and undergoes a structural change in a chemical reaction is a reactant. | A reagent is a substance added to reactions intending to bring chemical changes. Sometimes it tests a reaction's progress and product formation(s). Therefore, it may or may not be consumed in a reaction. |
The Atomic number (symbol Z) uniquely identifies an element and is equal to the number of protons present in the nucleus of an atom.
For example, atomic number 6 identifies the Carbon atom with 6 protons in its nucleus. An uncharged Carbon atom will also have 6 electrons in the outer nuclear region, equal to its atomic number.
Learning Objective: To calculate the number of active hydrogen bonds per molecule and techniques for detecting hydrogen bonds.
Skill Level – Intermediate
Prerequisites:
Alpha hydrogens