Atoms, elements, molecules, compounds Flashcards
What is an atom?
An atom is the smallest particle of a chemical element that can exist.
Define an element
An element is a substance made up of only one type of atom.
What type of atoms does an element contain?
Elements contain all the same type of atom. For e.g. gold is an element and it contains only gold atoms.
What type of atoms is the element helium made up of?
Helium atoms
All of the elements that exist are listed in the __________ ___________.
Periodic table
What is a compound?
A compound is a substance made up of atoms of 2 or more elements that are chemically bonded together.
Define a molecule…
- A molecule is made up of a small group atoms of the same element bonded together. - Made up of only non-metal atoms.
- Can also be an element.
e. g. O2 is a molecule
Name the elements present in the compoud K2SO4
K = potassium
S = Sulphur
0 = Oxygen
How many hydrogen and oxygen atoms are present in a molecule of water (H2O)
2 Hydrogen atoms
1 Oxygen atom
Vinegar (that you put on your chips) is a compound! It has the chemical formula CH3COOH.
How many different elements are present in this compound?
There are 3 different elements.
Carbon, hydrogen and Oxygen
Ammonia has the chemcial formula NH3.
Which elements (and how many) are present in this compound.
Ammonia (NH3) contains 2 elements: Nitrogen and hydrogen.
Ammonia contains 1 nitrogen atom and 3 hydrogen atoms.
What type of substance is carbon dioxide and why?
Carbon dioxide is a compound.
It is a compound because it contains 2 or more elements chemically bonded together.
What type of substance is shown in the diagram?
Why did you choose this answer?
The substances is an element.
It is an element because it is made up of only one type of atom.
Which element has the chemical symbol Cl
(*Use your periodic table if you’re not sure)
Chlorine
Which element has the chemical symbol Na
(*Use your periodic table if you’re not sure)
Sodium
Which element has the chemical symbol Mg
(*Use your periodic table if you’re not sure)
Magnesium
Which element has the chemical symbol K
(*Use your periodic table if you’re not sure)
Potassium
Which element has the chemical symbol Fe
(*Use your periodic table if you’re not sure)
Iron
Which element has the chemical symbol O
(*Use your periodic table if you’re not sure)
Oxygen
Which element has the chemical symbol B
Boron
Which element has the chemical symbol Al
Aluminium
Which element has the chemical symbol F
Flourine
Which element has the chemical symbol Ne
Neon
Which element has the chemical symbol P
Phosphorus
Which element has the chemical symbol Li
Lithium
Which element has the chemical symbol H
Hydrogen
1) Which elements make up the compound:
Hydrogen chloride
2) What is the chemical formula of hydrogen chloride
1) Hydrogen and chlorine
2) HCl
1) Which elements make up the compound:
Carbon dioxide
2) What is the chemical formula of carbon dioxide
1) Carbon and oxygen
2) CO2
1) Which elements make up the compound:
Potassium flouride
2) What is the chemical formula of potassium flouride
1) Potassium and flourine
2) KF
1) Which elements make up the compound:
Zinc Oxide
2) What is the chemical formula of Zinc oxide?
1) Zinc and Oxygen
2) ZnO
What type of substance is shown in the diagram?
The diagram shows molecules of hydrogen.
Hydrogen is also an element.
What type of substance is shown in the diagram?
Why do you think it is this substance?
This substance is a compound.
It is a compound because it is made up of more than 2 elements chemically bonded together.
What is the chemical formula for water?
H2O
What is the chemical formula for sulphur dioxide?
SO2
What is the chemcial formula for a molecule of oxygen?
O2
What is the chemical formula for magnesium oxide?
MgO
What is the chemical formula for sodium chloride?
NaCl
What is the chemical formula for a molecule of nitrogen?
N2
