An acid can be described as "strong" or "dilute" based on different factors. The strength of an acid refers to the extent to which it dissociates in water, with a strong acid being one that dissociates almost completely. On the other hand, an acid is considered dilute based on its concentration in solution, which refers to how much acid is dissolved in water.

A strong but dilute acid is one that dissociates nearly completely but has a low concentration. For example, a 0.01 mol/dm³ sulfuric acid solution is strong due to its complete dissociation but dilute because of its relatively low concentration.

Alkali metals belong to Group 1 of the periodic table, which means they have a single electron in their outermost shell. To achieve a stable noble gas configuration, these elements seek to lose this electron. Since it requires very little energy to remove this lone electron, alkali metals react vigorously with other substances in an attempt to achieve a more stable electron configuration.

A Bronsted-Lowry acid is defined as a proton donor. In aqueous solution, it can dissociate by releasing a hydrogen ion (H+), which is essentially a proton. This process results in the formation of a negatively charged anion as the proton is donated.

Cracking is a chemical process in which large hydrocarbon molecules are broken down into smaller, more useful molecules, typically using a catalyst. This process results in the formation of alkanes and alkenes.

Alkanes are hydrocarbons that contain only single bonds between carbon atoms.

Alkenes, on the other hand, contain at least one double bond between carbon atoms, with the remaining bonds being single bonds.

Cracking is commonly used in the petroleum industry to produce shorter-chain hydrocarbons that are in higher demand, such as gasoline and diesel.

A substance that facilitates a chemical reaction by offering an alternative pathway, which requires less energy than the reaction's activation energy.

Ionic bonding occurs when a metal and a non-metal ion, carrying opposite charges, are attracted to each other through electrostatic forces. For example, in sodium chloride (NaCl), a sodium atom (Na) loses an electron to become a positively charged ion (Na+), while a chlorine atom (Cl) gains that electron to become negatively charged (Cl-). The oppositely charged ions attract and form a giant ionic lattice.

Covalent bonding, on the other hand, involves two atoms sharing a pair of electrons. This sharing allows each atom to achieve a full outer electron shell. For instance, in a Cl₂ molecule, two chlorine atoms, each one electron short of a complete outer shell, share their last unpaired electrons to form a covalent bond.

Metallic bonding involves the attraction between metal ions and a 'sea' of delocalized electrons. In a sample of magnesium (Mg), each magnesium atom loses its two outer electrons, becoming Mg²⁺ ions. These electrons become part of the delocalized electron cloud, and the electrostatic attraction between the positively charged metal ions and the free-moving electrons creates metallic bonds, giving metals their unique properties.

Crude oil is a complex mixture of organic molecules containing carbon with varying chain lengths. These different chain lengths result in different boiling points: longer molecules, with stronger intermolecular forces, have higher boiling points and are less volatile compared to shorter molecules. This variation in boiling points allows the components of crude oil to be separated into fractions with similar boiling points through a process known as fractional distillation.

In fractional distillation, the column is designed with a temperature gradient, being hottest at the bottom and coolest at the top. The more volatile, less viscous fractions, such as gasoline (petrol), condense near the top of the column, while the less volatile, more viscous fractions, such as bitumen, remain liquid and separate at the bottom. Thus, the process effectively separates crude oil into fractions based on their volatility and viscosity.

A covalent bond forms between non-metal atoms when they share electrons from their outer electron shells. This electron sharing allows each atom to achieve a stable configuration, similar to that of an inert gas, by filling its outer shell.