What Makes an Atom
What three particles make up an atom?
Protons, neutrons, and electrons
An atom has 1 proton. What element is it?
Hydrogen
What is an ion?
An atom that has gained or lost electrons
Why are protons and electrons attracted to each other?
Opposite charges attract
What does the atomic number tell you?
The number of protons
Which particle determines what element an atom is?
The number of protons
An atom has 8 protons. What element is it?
Oxygen
What is an isotope?
Atoms of the same element with different numbers of neutrons
Why do elements in the same group on the periodic table react similarly?
They have the same number of valence electrons
What does the mass number represent?
The number of protons + neutrons
Where are protons and neutrons found in an atom?
In the nucleus
An atom has 6 protons and 6 neutrons. What element and isotope is it?
Carbon-12
An atom that loses electrons becomes what?
A positive ion (cation)
If an atom has equal protons and electrons, what is its overall charge?
Neutral
What do we call the outermost electrons of an atom?
Valence electrons
Where are electrons found?
In energy levels (electron cloud) around the nucleus
An atom has 11 protons and 10 electrons. What element and charge does it have?
Sodium ion (Na⁺)
An atom that gains electrons becomes what?
A negative ion (anion)
Why do atoms form chemical bonds?
To become stable by filling their outer electron shells
Which subatomic particle has the smallest mass?
Electron
What happens to the atom’s charge if you add one extra electron?
It becomes negatively charged (an ion)
An atom has 26 protons. What element is it, and what happens if you add 2 more electrons?
Iron (Fe); it becomes Fe²⁻
A neutral atom has 10 protons and 10 electrons. What happens if you remove one electron?
It becomes a +1 ion
What do you get when atoms of two different elements join together?
A molecule
What do all atoms of the same element have in common?
The same number of protons