Exploring the World of Chemistry

What is the basic unit of matter?

• molecule

• atom

• cell

• electron

What is the chemical symbol for water?

• H2O2

• O2H

• H2O3

• H2O

What do we call a substance made of two or more elements?

• compound

• element

• mixture

• solution

What is the pH scale used for?

• The pH scale is used to measure the acidity or alkalinity of a solution.

• To measure the temperature of a solution.

• To assess the viscosity of a solution.

• To determine the color of a solution.

What is the process of a solid turning into a liquid called?

• Condensation

• Freezing

• Melting

• Sublimation

What is the name of the gas that plants take in during photosynthesis?

• Nitrogen

• Carbon dioxide

• Oxygen

• Hydrogen

What is the chemical formula for table salt?

• NaCl

• MgCl2

• CaCl2

• KCl

What is an atom?

• A fundamental force that holds matter together.

• An atom is the smallest unit of matter that retains the properties of an element.

• A type of chemical reaction between elements.

• A large collection of molecules that form a substance.

What is the difference between an element and a compound?

• An element can be made of multiple types of atoms, while a compound is made of a single type of atom.

• Elements can be broken down into simpler substances, whereas compounds cannot.

• A compound is a pure substance, while an element is a mixture of different substances.

• An element consists of one type of atom, while a compound consists of two or more different types of atoms chemically bonded.

What is the term for a mixture that has a uniform composition?

• Compound

• Solution

• Homogeneous mixture

• Heterogeneous mixture