What is the smallest unit of an element?
Atom
What is a combination of two or more substances that are not chemically bonded?
Mixture
What do we call a substance made of two or more different elements that are chemically bonded?
Compound
What property describes a substance's ability to conduct electricity?
Electrical conductivity
What is the pH range of acids?
0-6.9
Name one of the two main categories of elements in the periodic table.
Metals or Nonmetals
What type of mixture has a uniform composition throughout?
Homogeneous mixture
What type of bond holds the atoms in a compound together?
Chemical bond
Name a physical property that can be used to identify an unknown substance.
Color, odor, melting point, or density
What is the pH range of bases?
7.1-14
How many naturally occurring elements are there?
92
What is an example of a heterogeneous mixture?
Salad or sand and iron filings
Give an example of a compound that is a salt.
Sodium chloride (NaCl)
What is the term for the ability of a substance to be hammered into thin sheets?
Malleability
What is an example of a common household acid?
Vinegar (acetic acid)
Which element is represented by the symbol 'O'?
Oxygen
What do we call a mixture in which one substance is dissolved in another?
Solution
What is the chemical formula for water?
H₂O
Which property describes how easily a substance can be dissolved in water?
Solubility
What is the term for a substance that changes color in response to pH?
Indicator
What is the term for elements that are found in group 18 of the periodic table?
Noble Gases
What is the term for the process of separating a mixture by passing it through a filter?
Filtration
What is the process called when a compound breaks down into its elements?
Decomposition
What is the difference between a physical change and a chemical change?
A physical change does not alter the substance's chemical composition, while a chemical change does.
What is the result of mixing an acid with a base?
Neutralization, producing a salt and water.