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44 terms

Chemistry Section

ionic compounds
a compound composed of oppositely charged ions
Periodic Table
a tabular display of the chemical elements, which consists of rows and columns
Valence Shells
the outermost electron shell of an atom
Molecular Compounds
a compound made up of 2 or more non-metal elements
Vertical columns in the periodic tables
a chemical reaction, which absorbs heat energy from the surroundings
Physical Change
a change in the physical appearance of a substance after a chemical reaction
Chemical Equation
a symbolic representation of a chemical reaction in which the reactants are present on the left side and the products on the right side.
charged particle
horizontal rows in the periodic table
Ionic bonds
bonds created between a metal and non-metal due to the full transfer of electrons
the substances that are present before the chemical reaction begins and react to form new product/products
an ion, which has a positive charge and due to its positivity it, is attracted towards the negative electrode in electrolysis
a chemical reaction, which releases heat energy into the surroundings
Chemical Reaction
a process in which one or more reactants react together to form one or more products by the help of heat, electricity and catalyst
an electrically neutral group of 2 or more atoms which are held together by chemical bonds (covalent).
Valence electrons
electrons, which are present in the outermost shell of an atom and these, are the electrons, which are either transferred or shared with another atom to start a chemical reaction.
they help to reduce the activation energy by speeding up the chemical reaction
Covalent bonds
bonds formed between 2 non-metals due to the sharing of electrons
the end substances, which are formed in a chemical reaction after the reactants, have reacted
an ion having a negative charge
Law of conservation of mass
this states that mass is neither created nor destroyed and the mass of the reactants is always equal to the mass of the products.
the insoluble solid which is left behind at the end of the chemical reaction
Reactivity Series
this consists of a series of metals in order of their reactivity from the top to the bottom (top being the most reactive and bottom being the least reactive)
a compound which produces hydrogen ions (H+) when dissolved in water
a chemical compound that contains at least one oxygen atom and one another element.
Binary Acid
acids which are composed of 2 elements: 1 is hydrogen and the other is a non-metal e.g. HCl, HBr, HI. HF etc...........
Neutralization Reaction
a chemical reaction in which an acid and a base react together to produce salt and water, which are both neutral substances (pH at 7)
Rate of Reaction
the speed of a reaction i.e. how fast or slow a reaction takes place
they are biological catalysts that help to speed up a chemical reaction by reducing the activation energy
a bitter substance which has a pH value more than 7.
pH Scale
a scale with measurements used to determine the acidity or basicity of an aqueous solution
it consists of an oxygen atom bonded to a hydrogen atom and at least one more element
pH meter
an electronic instrument which is used to measure the acidity or basicity (pH) of a substance
:a chemical detector of protons in acid-base titrations
pH meter
an electronic instrument which is used to measure the acidity or basicity (pH) of a substance
a substance which is formed along with water when an acid and an alkali react together in a neutralization reaction.
Litmus Paper
an indicator, which is used to test whether, a solution is acidic or basic. The litmus paper turns red in acidic solutions and blue in basic solutions.
Surface Area
it is a measure of how much exposed area a solid has (measured in square units)
the strength of a solution which is measured in mol/dm3
combining of elements or molecules
splitting of molecules into smaller molecules or elements
Single displacement
one element replacing another element in a compound
Double displacement
two compounds switching there elements