Elements, Compounds, Molecules, and Mixtures

Multiple Choice

Which of the following best describes an element?

• A pure substance that cannot be separated into simpler substances by physical or chemical means.

• A mixture of two or more substances.

• A substance that can be separated by physical means.

• A compound made of different elements.

Multiple Choice

The periodic table is a list of all elements that can build ___.

• sound
• matter
• light
• energy

Multiple Choice

Which of the following statements about compounds is correct?

• Compounds are made of two or more different elements joined by chemical bonds.

• Compounds can be separated by physical means.

• Compounds are always made of the same element.

• Compounds do not have a specific ratio of elements.

Multiple Choice

Which of the following is formed when sodium reacts with chlorine?

• Sodium chloride

• Hydrogen chloride

• Sodium hydroxide

• Chlorine gas

Multiple Select

Which of the following are examples of compounds?

• Paper

• Nail Polish

• Candle

• Oxygen

Multiple Choice

Which of the following statements best describes the difference between organic and inorganic compounds?

• Organic compounds contain carbon, usually bonded to hydrogen, while inorganic compounds usually do not contain carbon.

• Organic compounds are always found in living things, while inorganic compounds are not.

• Inorganic compounds are always more complex than organic compounds.

• Organic compounds are always gases, while inorganic compounds are always solids.

Multiple Choice

A molecule is the smallest unit of a chemical substance that retains its chemical and physical properties, consisting of two or more atoms held together by chemical ___ .

• bonds
• mixtures
• compounds
• elements

Multiple Choice

Which of the following molecules consists of atoms of the same element?

• Oxygen (O2)

• Water (H2O)

• Sodium chloride (NaCl)

• Carbon dioxide (CO2)

Multiple Select

Which of the following are examples of molecules?

• Oxygen (O2)

• Glucose (C6H12O6)

• Caffeine (C8H10N4O2)

• Pizza

Multiple Choice

A mixture is made when two or more substances are combined, but they are not combined ___ .

• chemically
• temporarily
• physically
• uniformly

Multiple Choice

Which of the following is a characteristic of a heterogeneous mixture?

• The substances are evenly distributed.

• The substances are not evenly distributed.

• It contains only one type of atom.

• It cannot be separated by physical means.

Multiple Choice

According to the matter flowchart, what type of matter cannot be separated by physical means and cannot be decomposed by chemical means?

• Compound

• Element

• Homogeneous mixture

• Heterogeneous mixture

Multiple Choice

Which of the following best describes a homogeneous mixture?

• A mixture with uneven distribution of components

• A mixture with very large particles

• A mixture with even distribution of components and very small particles

• A mixture where particles settle quickly

Multiple Select

Which of the following are examples of homogeneous mixtures?

• Coffee

• Granite

• Steel

• Blood

Multiple Choice

A heterogeneous mixture is characterized by an ___ distribution of components.

• uniform
• even
• uneven
• consistent