Chemistry Chapter 1 Atomic Structure Flashcards
What are all substances made from?
All substances are made from atoms.
What do elements contain only 1 type of?
Elements contain only one type of atom.
What is the name of the diagram used to list all elements in order?
Elements are listed in the periodic table.
What is on the periodic table to distinguish between different elements?
Each element has a name and a symbol.
What is the correct way to write the symbol for an element?
The symbol for an element always starts with a capital letter but may have lower case letter too.
Example: Sodium = Na
Nitrogen = N
Copy and complete the table to give the symbols for the first 20 elements.
Name of Element
Symbol
Hydrogen
Helium
Lithium
Beryllium
Boron
Carbon
Nitrogen
Oxygen
Fluorine
Neon
Sodium
Magnesium
Aluminium
Silicon
Phosphorus
Sulfur
Chlorine
Argon
Potassium
Calcium
The names and symbols for the first 20 elements are:
Hydrogen
H
Helium
He
Lithium
Li
Beryllium
Be
Boron
B
Carbon
C
Nitrogen
N
Oxygen
O
Fluorine
F
Neon
Ne
Sodium
Na
Magnesium
Mg
Aluminium
Al
Silicon
Si
Phosphorus
P
Sulfur
S
Chlorine
Cl
Argon
Ar
Potassium
K
Calcium
Ca
How is the periodic table arranged?
The periodic table is an arrangement of elements in groups and periods.
What are groups in the periodic table and how many are there?
Groups are the columns in the periodic table. There are 8 groups.
How are elements in the same group similar?
Elements in the same group will have similar chemical properties.
There is a ‘step’ in the periodic table. What type of elements are on the left of the step and what type are on the right?
The periodic table has a ‘step’ that separates metals from nonmetals. Metals are on the left of the step and nonmetals are on the right.
What are the ‘periods’ in the periodic table?
Periods are rows in the periodic table.
Give the definition for a compound and give an example of a compound.
Compounds contain more than one type of atom. This means they have more than one element.
Example: Carbon dioxide is a compound CO2
What do the letters and numbers in a chemical formula represent?
The letters in a chemical formula represent the element present. The numbers tell up how many atoms of each element there are.
Example: CO2 has 1 carbon atom and 2 oxygen atoms
How can compounds be separated into elements?
Compounds can only be separated into elements by chemical reactions.
What name do we give to the chemicals that react together in a chemical reaction?
Chemicals that react together are called reactants.
What name do we give to the chemicals that are produced in a chemical reaction?
Chemicals that are produced in a chemical reaction are called products.
When writing a chemical equation what symbol do we use to separate the reactants and the products?
The reactants and products are separated by an arrow in a chemical equation.
reactants → products
Why does the number of atoms of one element in the reactants need to be the same as the number of atoms of that element found in the products?
The number of atoms of one element in the reactants is the same as the number of atoms of that element in the products. This is because in a chemical reaction atoms cannot be created or destroyed. They are only rearranged.
State the law of conservation of mass.
The law of conservation of mass states that “The total mass of the products formed in a reaction is equal to the total mass of the reactants.”
What can we do to a chemical equation to make sure the number of atoms in the reactants is the same as the number of atoms of each element in the products?
Equations must be balanced to make sure the number of atoms of each element in the reactants is the same as the number of atoms of each element in the products.
Where do we add numbers to a chemical equation to balance it?
To balance an equation a number can be added to the front of the symbol for a reactant or product. The chemical formula for a compound or molecule cannot be changed.
Example:
Unbalanced: H2 + O2 → H2O
Balanced: H2 + 2O2 → 2H2O
The formula for water cannot be changed from water: H2O to peroxide: H2O2.
What do chemical reactions always result in?
Chemical reactions always result in the formation of one or more new substances.
What are the 4 states identified in chemical equations using state symbols?
State symbols are used to show whether a chemical is a solid, liquid, gas or aqueous.
What does aqueous mean?
Aqueous means dissolved in water.
Complete the table to show the state symbols:
State
Symbol
solid
liquid
gas
aqueous
The state symbols are:
What is a mixture?
A mixture is made up of 2 or more substances that are not chemically combined together.
What is a pure substance?
A pure substance is made up of only one type of element or compound.
What is an impure substance?
An impure substance is a mixture of elements or compounds.
How can compounds in mixtures be separated from each other?
The compounds in mixtures can be physically separated from each other.
Give 3 methods of separating mixtures.
Methods of separating mixtures include: filtration, crystallisation and simple distillation.