Chemistry key terms

A six-membered arrangement of bonded atoms forming a ring.

The largest whole number that divides every number in a ratio exactly.

A family of compounds with similar structures and the same general formula.

A compound that contains water molecules within its crystal structure.

A crystal containing water as part of its crystal structure.

A crystalline compound containing water as part of its crystal structure.

A substance that contains water as part of its crystal structure.

A compound whose molecules contain carbon and hydrogen atoms only.

A fuel containing hydrocarbons, which are compounds made from carbon and hydrogen only.

A gas produced when lithium, sodium or potassium reacts with water.

A compound of hydrogen and a halogen, with the general formula HX, where X represents a halogen.

A positively charged ion, written $\mathrm{H^+}$, produced by acids in aqueous solution.

The amount of hydrogen ions, $H^+$, present in a given volume of solution.

A fuel cell in which hydrogen reacts with oxygen, transferring chemical energy mainly as electrical energy and producing water.

A negatively charged ion with the formula OH⁻. Hydroxide compounds are included in these solubility rules, although hydroxides are not salts.

A negatively charged ion, OH⁻, supplied by an alkali in solution.

The –OH group found in an alcohol molecule.

A prediction that can be tested by an investigation.

An ending commonly used for a compound containing two elements, such as sodium chloride or magnesium oxide.

Liquids that do not mix and form separate layers.

An unwanted substance mixed with the substance being examined.

The disposal of waste by burning it at a high temperature.

Combustion in a limited supply of oxygen, which can produce carbon monoxide, solid carbon and unburned fuel as well as water.

A reaction that has not proceeded to the theoretical extent expected from the limiting reactant, so less desired product forms.

An increase in the mass of crop harvested from an area of land.

The variable deliberately changed during an investigation.

The power in an expression such as $10^n$; it shows how many places the digits change in place value.

A substance that changes colour depending on whether a solution is acidic, neutral or alkaline.

A collision in which the total kinetic energy of the colliding objects is not conserved because some is transferred to other energy stores.

A sphere that does not change shape when forces act on it.