Chemistry Key Terms Flashcards
What is: an ACID
A molecule that releases H⁺ ions in water
What is: Activation energy
The minimum energy barrier which must be overcome before particles that can collide can react
What is: Atom
The smallest unit of matter
What is: Atomic number
Defines the element, gives the number of protons (& hence electrons) and tells you the position on the periodic table.
What is: a BASE
A molecule that releases hydroxide ions (OH⁻) in water or reacts with water to form OH⁻ ions.
What is: a Catalyst
Any substance which increases the rate of reaction by lowering the activation energy.
What is: Collision theory
The set of rules that determine whether a successful collision between particles,and therefore a reaction, will occur: “particles must collide with enough energy and in the right orientation for a successful collision to occur.”
What is: Concentration
The amount of particles in a set volume. e.g 0.15molL¯¹
What is: Electron arrangement
How you show how many electrons are in each shell of an atom. The electron arrangement rule is: 2,8,8
What is: The Electron shell
Where the electrons are held they are contained in the shells and orbit the nucleus of the atom.
What is: Electrons
Small particles that are contained in an atoms shell and orbit the nucleus, they have a negative charge.
What is: Universal Indicator
A solution that you use to determine whether a solution is acidic, neutral or basic (a base). It turns the colour of the pH of the solution.
What is: Litmus paper
Used to show you whether a solution is acidic, neutral or basic (a base) there is blue litmus paper and red litmus paper. Blue stays blue in a base or neutral and turns red in an acid. Red stays red in an acid or neutral and goes blue in a base.
What is: An ion
An atom or group of atoms with a charge positive (+) or negative (-). An atom becomes an ion by GAINING or LOSING ELECTRONS in order to have a FULL OUTER/VALENCE SHELL in order to be STABLE.
What is: An ionic bond
The electrostatic attraction which holds together a positively charged ion (cation) and a negatively charged ion (anion).
What is: An ionic compound
Formed from combining a POSITIVE and NEGATIVE ion. MUST be NEUTRAL in charge.
What is: Mass number
The number of protons and neutrons together.
What is: A neutralization reaction
A reaction between an ACID and a BASE which produces a SALT and WATER.
What is: A neutron
A particle that is neutral in charge. It is found in the nucleus/center of an atom.
What is: Nucleus
The center of an atom where the protons and neutrons are found.
What is: pH scale
A scale from 0-14 that measures how acidic, neutral or basic a solution is. 0-2 is red=STRONG ACID, 3-4 is orange=WEAK ACID 5-6 is yellow=WEAK ACID, 7 is green=NEUTRAL, 8-11 is blue=WEAK BASE/ALKALI, 12-14 is purple=STRONG BASE/ALKALI
What is: pH
A measurement of how many H⁺ ions there are compared to how many OH⁻ ions there are.
What is: Proton
A particle with a positive (+) charge. It is located in the nucleus/center of an atom.
What is: Rate of reaction
The rate is how quickly chemicals react. In order for 2 chemicals to react they have to COLLIDE with enough energy and correct orientation. PARTICLES will be used to describe any element or compound (e.g Mg or HCl). The rate of reaction is the NUMBER OF REACTIONS per second/or per unit of time. the factors effecting the rate of reaction are: SURFACE AREA, TEMPERATURE, CONCENTRATION and CATALYSTS.
What is: Valence electrons
The electrons found in the valence shell/outer shell of an atom.
What is: Valence shell
The outer shell of an atom
