atomic structure
What particle has a positive charge
what is proton
What family of elements is extremely unreactive?
Noble gases
What type of bond involves sharing
covalent bonds
What must happen to a chemical equation before solving stoichiometry problems?
It must be balanced
What element do humans need to breathe?
Oxygen
What pH number is considered neutral?
7
Atoms of the same element always have the same number of what?
protons
What family contains very reactive metals?
Alkali metals
What is formed when an atom gains or loses electrons?
an ion
What unit represents 6.022 × 10²³ particles?
a mole
What element’s symbol is Au?
Gold
What common citrus fruit contains acid?
Lemon
What do you get when you add protons and neutrons together?
Atomic mass
Elements in the same column have the same number of what?
Valence electrons
What type of bond is found in water (H₂O)?
Covalent
In the equation 2H₂ + O₂ → 2H₂O, how many molecules of water are produced?
2 moles
What common molecule is known as H₂O?
water
What ion do acids release in water?
Hydrogen ions (H⁺)
What happens to an atom if it gains electrons?
It becomes negatively charged
What side of the periodic table are metals usually found on?
the left side
Why do atoms bond with each other?
To become stable / fill their valence shells
What is the limiting reactant?
The reactant that runs out first
What element do pencils contain?
Carbon
What color does blue litmus paper turn in an acid?
Red
True or False: Electrons are larger than protons
false
What is the most abundant gas in Earth’s atmosphere?
Nitrogen
What bond forms when electrons are shared unequally?
Polar covalent bonds
What law says matter cannot be created or destroyed?
Law of Conservation of Mass
What element is used in nuclear power plants as fuel?
Uranium
What type of reaction occurs when hydrochloric acid reacts with sodium hydroxide?
Neutralization