Atomic Structure
What is the charge and location of each subatomic particle in an atom?
Proton (+, nucleus), Neutron (0, nucleus), Electron (−, shells)
A: Proton, neutron, electron
What are the three subatomic particles in an atom?
What does a chemical symbol represent and give an example?
A one- or two-letter abbreviation for an element, e.g., O for oxygen
A: Acid + base → salt + water
What is the general word equation for a neutralisation reaction?
What are two signs that a chemical reaction has occurred?
Color change, gas production, temperature change, precipitate forms
What does the atomic number tell you about an atom?
The number of protons in the nucleus
A: Atoms of the same element with different numbers of neutrons
What are isotopes?
What is the difference between a molecule and a compound?
A molecule is two or more atoms bonded - the same element, or different elements;
a compound is a molecule with different elements bonded
A: A hydrocarbon reacts with oxygen to form CO₂ and H₂O
What is a combustion reaction?
What are the products of a reaction between an acid and a metal?
Salt and hydrogen gas
How many electrons are in each shell of a fluorine atom (atomic number 9)?
2 in the first shell, 7 in the second
A: Alpha, beta, and gamma
What are the three types of nuclear radiation?
How many atoms and how many elements are in the compound H₂SO₄?
7 atoms total; 3 elements (H, S, O)
A: HCl + NaOH → NaCl + H₂O
Give an example of a chemical equation for a neutralisation reaction.
Write a word equation for the reaction between magnesium and hydrochloric acid.
Magnesium + hydrochloric acid → magnesium chloride + hydrogen
What is the difference between a neutral atom and an ion?
A neutral atom has equal protons and electrons; an ion has gained or lost electrons
A: The electron configuration 2,8,1
What is the electron configuration of sodium?
How many atoms and how many different elements are in the compound NaHCO₃?
6 atoms total; 4 different elements
A: One element replaces another element in a compound during a chemical reaction
What is a single displacement reaction?
Identify the type of reaction: AB + CD → AD + CB
Double displacement reaction
What happens to the atomic number, mass number, and identity of an atom during alpha decay? Give an example using the alpha decay of radium-226.
The atomic number decreases by 2 and the mass number decreases by 4, because an alpha particle (2 protons and 2 neutrons) is emitted. The atom becomes a different element.
Radium-226 (atomic number 88) undergoes alpha decay to become radon-222 (atomic number 86).
A: A nucleus emits a particle and transforms into a different element
What is nuclear decay?
Why are elements arranged in rows and columns on the Periodic Table?
Rows (periods) show increasing atomic number and energy levels; columns (groups) contain elements with similar chemical properties and the same number of valence electrons.
A: A reaction that forms an insoluble solid from two solutions
What is a precipitation reaction?
A white solid forms when two clear solutions are mixed. What type of reaction is this?
Precipitation reaction