Review 4: SC.8.P.8.5 - SC.8.P.9.2 - SC.7.P.10.1

(SC.8.P.8.5) Atoms combine in many different ways to form different substances. Iron is an element. Brass is not an element, instead brass is a combination of two elements. What is the difference between iron and brass?

• Iron is a compound, brass is not.
• Brass is a compound, iron is not.
• Iron, but not brass, consists of atoms.
• Brass, but not iron, is a metallic substance.

(SC.8.P.8.5) Which of the following is a property of elements?

• Elements have at least two different types of atoms.
• Elements are can be separated from one another.
• Elements have their own individual characteristic properties.
• Elements have the ability to change into a different element.

(SC.8.P.8.5) The drawing below illustrates a chemical process. What chemical process does the drawing best illustrate?

• Atoms of different elements combining to form a compound.
• Elements breaking up into atoms.
• Compounds combining to form elements.
• Elements combining to form other elements.

(SC.8.P.8.5) A compound consists of two or more elements that have combined. Which of the following compounds contains three different elements?

• O3
• H2SO4
• MgO
• H2O

(SC.8.P.8.5) Compounds are made up of different kinds of atoms that are chemically combined. What do compounds have in common?

• They cannot combine with one another to form more complex substances.
• They can be broken down into simpler substances.
• They have the same melting point.
• They have the same color.

(SC.8.P.8.5) Robert and Daniela are discussing the phases of water. Robert says that ice, water, and steam are three different compounds since they have three different names. Daniela disagrees and says that all three states are the same compound. Who is correct and why?

• Daniela is correct because all three states are made of the same compound with the same ratio of hydrogen to oxygen.
• Robert is correct because unique names are only given to new compounds that are discovered.
• Daniela is correct because all three states of water have the same physical properties.
• Robert is correct because the three states of water have different physical properties.

(SC.8.P.8.5) The model below represents a structure of a form of matter. Which of the following does the model represent?

• a nucleus
• an element
• an atom
• a compound

(SC.8.P.8.5) Both carbon dioxide (CO2 ) and glucose (C6H12O6) are molecular compounds. Which one of the two compounds is organic?

• Only the carbon dioxide molecule is organic.
• Both molecules are organic.
• Only the glucose molecule is organic.
• Neither of the molecules is organic.

(SC.8.P.8.5) Study the chemical formulas of the two different compounds listed below. What can you conclude about these compounds from their chemical formulas?

• Each compound contains unique elements.
• All compounds contain at least three elements.
• The same elements can combine in different ways to make compounds.
• All compounds contain the same elements.

(SC.8.P.8.5) An element is also a pure substance. What is the reason for this?

• There are many ways that elements can combine.
• An element can combine with another element.
• An element contains only one type of particle.
• Different elements have different properties.