Chemical Reactions Unit Exam

Which of the following models best demonstrates a balanced chemical equation?

• F
• G
• H
• J

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The formula below represents the most common carbohydrate known as glucose. Which information can be determined from the chemical formula?
C₆H₁₂O₆

• The structural arrangement of the atoms in a glucose molecule
• The color of a glucose molecule
• The size of a glucose molecule
• The number of atoms of each element in a glucose molecule

Tags

NGSS.MS-PS1-1

For an investigation a student poured a blue solution of CuSO₄ into a beaker. The student placed a shiny, silver-colored strip of zinc metal in the solution and observed the changes. The metal turned black and there were bubbles.

The student inferred that a chemical reaction occurred. What evidence supports this inference?

• A dark solid formed on the zinc metal and a gas was released

• The zinc metal remained silver-colored and shiny

• The CuSO₄ solution turned blue when the zinc metal was added.

• None of these

Tags

NGSS.MS-PS1-2

The reactants are on the left side of the chemical equation.

• True
• False

In which of these compounds are there twice as many oxygen atoms as hydrogen atoms?

• H₃PO₄
• H₂SO₄
• HCIO₃
• H₂0

Tags

NGSS.MS-PS1-1

Coal contains carbon and other elements. During a combustion reaction, Carbon Dioxide forms when coal burns in the presence of oxygen. Which of these is the best evidence that a chemical reaction occurs when coal burns?

• The shape of the coal changes

• Oxygen is present

• A new substance is produced

• Coal is made up of more than one element

Tags

NGSS.MS-PS1-2

In a ___________change, a substance changes into a different substance.

• Physical

• Chemical

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The Law of Conservation of Mass states

• that matter exists in all states and reacts the same

• that matter can only be changed into new substances by introducing a catalyst

• that matter exists in the same state throughout any chemical change

• that matter cannot be created or destroyed and that the mass of the products must equal the mass of the reactants

Tags

NGSS.MS-PS1-5

How many Al atoms are in this compound? 4Al₂O₃

• 3

• 8

• 6

• 4

Tags

NGSS.MS-PS1-1

a copper penny turning greenish after a few years. Is this a physical or chemical change?

• Physical change

• Chemical change

Tags

NGSS.MS-PS1-2