Study for the 6th grade final at OHJH

To explain the difference between elements and compounds, a teacher filled clear boxes with balls. Which box best represents a sample of an element?

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What is an element made of?

• An element is made up of two or more atoms that have names all start with the same letter.

• An element is made up of two types of atoms that are always proportional.

• An element is made up of two types of atoms that are joined in a particular molecular structure.

• An element is a pure substance and only made up of one type of atom.

Components of our environment can be classified as elements, compounds, or mixtures.

Select TWO correct answers.

• gold ring

• salt

• water

• aluminum can

• sand

Which element, that is essential for human life, is found in large amounts in both Earth's atmosphere and oceans?

• calcium

• helium

• oxygen

• silver

The pie chart on the left shows the percentage of elements in the human body. The pie chart on the right shows the percentage of elements in the earth's crust. According to the chart, what element (other than oxygen) do the two charts have in common?

• oxygen

• calcium

• potassium

• nitrogen

Is baking a cake a

• chemical change

• physical change

• no change

Cutting an apple is a

• chemical change

• physical change

• no change

Lucy and Carlos were conducting a lab to identify possible evidence of chemical changes of matter. They began by combining two substances in a zip bag. They observed the zip bag filling up with gas and the temperature of the combined substances begins to drop. Identify the evidence that supports a possible chemical change had taken place. Select TWO correct answers.

• The substances were put in the zip bag together, then the zip bag was closed.

• The temperature of the combined substances dropped.

• The zip bag filled up with gas.

• They added the substances to the zip bag.

A solid produced by a chemical reaction in solution that separates from the solution is called

• an element

• a precipitate

• a solution

• a twofersolution

Which is not a good characteristic to use to determine a type of mineral?

• color

• hardness

• luster

• shape