Formulae,equations,hazards Flashcards
What’s an element
Substance made from atoms with the same number of protons in the nucleus
What’s an atom
Smallest particle of an element that still has its chemical properties
What’s a molecule
Two or more atoms chemically joined together
Most elements that are gases at room temperature exist as
Molecules with two atoms
H2 N2 O2 F2 Cl2
Chemical formula for methane
CH4
What’s an ion
Atom or group of atoms gain or lose an electron and from a positive or negative charge
When writing ionic equations
All substances are shown by their formula
Number of atoms of each element in the reactants and products are the same
Total electrical charge is the same on both sides of the equation
Oppositely charged ions in a solution may join to form a…
Insoluble solid called a precipitate
What’s a hazard
Something that could cause damage or harm to someone or something
Adverse health effects which may occur immediately or later on
What’s a risk
The chance that someone or something will be harmed if exposed to a hazard
The amount of risk depends on factors such as
How much someone is exposed to a hazard
The way in which exposure happens
How serious the effects of exposure are
What’s a precaution
Something that you can do to reduce the risk of a hazard
What are hazard symbols intended to do
Warn about the dangers assosiacted with the substance in the container
Let people know about the precautions to take when they use the substance
Common hazard symbols
Harmful/irritant Toxic Flammable Corrosive Respiratory sensitiser Oxidising
Hydrogen + hydroxide =
Water
