What is a characteristic of elements as described in the passage?

• They can be broken down chemically.

• They are represented by a chemical formula.

• They are pure substances.

• They are not found on the Periodic Table of Elements.

Which of the following is an example of a homogeneous mixture?

• Salad

• Coffee

• Water and oil

• Sand and salt

What distinguishes compounds from elements according to the passage?

• Compounds are pure substances, while elements are not.

• Compounds can be broken down chemically, while elements cannot.

• Compounds are found on the Periodic Table, while elements are not.

• Compounds have the same properties as the elements that make them up.

Which statement is true about mixtures based on the passage?

• Mixtures are composed of elements that are chemically combined.

• Mixtures cannot be separated.

• Mixtures undergo chemical changes when formed.

• Mixtures can be homogeneous or heterogeneous.

What is a common characteristic of both elements and compounds?

• Both are represented by a 1 or 2 letter chemical symbol.

• Both are pure substances.

• Both can be broken down chemically.

• Both are found on the Periodic Table of Elements.

According to the passage, what is a key difference between homogeneous and heterogeneous mixtures?

• Homogeneous mixtures have a uniform composition, while heterogeneous mixtures do not.

• Heterogeneous mixtures can be separated, while homogeneous mixtures cannot.

• Homogeneous mixtures undergo chemical changes, while heterogeneous mixtures do not.

• Heterogeneous mixtures are pure substances, while homogeneous mixtures are not.

Which of the following elements are mentioned as the most common in the universe?

• Oxygen and Carbon

• Hydrogen and Helium

• Nitrogen and Oxygen

• Carbon and Helium