Atoms and Combustion Test Flashcards
What is matter made of?
Tiny, indivisible particles named atoms
What are the three sub-atomic particles?
Protons, neutrons, electrons
What is the electrical charge of a proton?
+1
What is the electrical charge of a neutron?
0
What is the electrical charge of an electron?
-1
What is the mass of a proton (relative)?
1
What is the mass of a neutron (relative)?
1
What is the mass of an electron (relative)?
1/1840 of a proton
Where are protons located in the atom?
Nucleus
Where are electrons located in the atom?
Orbiting nucleus
Where are neutrons located in the atom?
Nucleus
What is the mass number, and what does it consist of?
Mass of an element, protons + neutrons (as they both have a mass of 1, electrons too small to count)
What is the atomic number?
Number of an element on the periodic table, according to the number of protons.
What are atoms mostly made of?
Empty space
What is a neutral atom?
When there is an equal number of electrons and protons (+1 and -1 charges balance out)
How do you calculate the proton number?
mass no - proton no OR atomic no
How do you calculate the neutron number?
mass - proton no
How many electrons can the first shell hold?
2
How many electrons can the second shell hold?
8
When does radioactivity occur?
When the atom’s nucleus is unstable.
In what atoms does radioactivity usually occur?
Atoms with large nuclei, eg radium, plutonium
What are the three types of radioactive decay?
Alpha, beta, gamma
What is alpha radiation?
When a nuclei “spits” out alpha particles, comprised of 2 protons and 2 neutrons. Therefore, they have a charge of +2
What is beta radiation?
When electrons are “spat” out from the nuclei.
What is gamma radiation?
A high-energy beam of light. The most deadly type of radiation as it can pass through surfaces easily and damage DNA
Rank the types of radiation in order from least to most deadly
Alpha, beta, gamma
What is the charge of alpha radiation?
+2 (two protons, neutrons no charge)
What is the charge of beta radiation?
-1 (one electron has a negative charge)
What is the charge of gamma radiation?
No charge
What does it take to stop alpha radiation?
Paper, air
What does it take to stop beta radiation?
Aluminium foil
What does it take to stop gamma radiation?
metres thick wall of concrete or lead
What is half-life?
The measure of the time it takes for half of a number of atoms to decay radioactively.
What is the half-life measured in? (units)
Seconds, days, years, or any period of time. Half-life can last from milliseconds to millions of years.
What is an isotope?
A type of atom that contains more neutrons than the element typically has. They differ therefore in atomic mass but their atomic number and charge is not affected.
What is an exothermic reaction?
Heat, produces heat, use and produce large amounts of energy
What is an endothermic reaction?
Colder temps absorb energy
What is a chemical reaction?
Where two reactants are combined, rearranging atoms therefore producing new products. WHAT YOU START WITH –> YOU END WITH
Signs of a chemical reaction?
Temperature change, bubbles (effervescence), colour change, smell, light, formation of gas, formation of a precipitate
