Atoms, elements and compounds Flashcards
What is the chemical symbol for sodium?
Na
Where are non-metals found in the periodic table?
On the right
What is a molecule?
Two or more atoms held together by chemical bonds
Name 7 elements that exist as molecules (go round in pairs).
- Iodine
- Bromine
- Chlorine
- Fluorine
- Oxygen
- Nitrogen
- Hydrogen
What is a compound?
A substance that contains two or more elements which are chemically combined
What is the formula for magnesium oxide?
MgO
What is the formula for carbon dioxide?
CO2
What is the formula for water?
H2O
What is the formula for methane?
CH4
What is the formula for ammonia?
NH3
What is an element?
A substance that contains only one type of atom
What is an ion?
A charged particle formed when an atom loses or gains electrons
What charge does an electron have?
A negative charge
Name the three subatomic particles that make up atoms.
- Protons
- Neutrons
- Electrons
What is the formula for a magnesium ion?
Mg2+
What is the formula for a chloride ion?
Cl-
What are reactants?
Substances that react together in a chemical reaction
What is a product?
A substance that is formed in a chemical reaction
Sodium and chlorine react together to make sodium chloride.
What is the word equation for this reaction?
sodium + chlorine → sodium chloride
What is the state symbol for a solid?
(s)
What is the state symbol for a liquid?
(l)
What is the state symbol for a gas?
(g)
What is the state symbol for an aqueous solution?
(aq)
What does aqueous solution mean?
Dissolved in water
What is meant by the law of conservation of mass?
No atoms are created or destroyed during a chemical reaction, so the mass of the reactants is equal to the mass of the products
