Chemical Equations & Chemical Reactions

Is this equation balanced or unbalanced?

CO_{2 --->} 2CO

• Balanced

• Unbalanced

In chemical reactions, what does the law of conservation of mass mean?

• Matter is not created or destroyed.

• The total mass of the reactants is greater than the total mass of the products.

• The total mass of the reactants is less than the total mass of the products.

• Matter is not changed.

How many molecules of Carbon are in the following formula? 3C₂H₆

• 3
• 6
• 12
• 18

Tags

NGSS.MS-PS1-1

How many elements are in C₆H₁₂O₆?

• 1
• 2
• 3
• 4

Tags

NGSS.MS-PS1-1

What is the  chemical formula for Glucose?

• GLc
• C₆H₁₂0₆
• G₁₂H₂C₆
• Glucose

Tags

NGSS.MS-PS1-1

How many Hydrogen (H) atoms are in NH₃O5

• 3
• 4
• 5
• 1

Tags

NGSS.MS-PS1-1

How many Oxygen (O) atoms are in 2C₂HO₈C_l2

• 2
• 16
• 8
• 5

Tags

NGSS.MS-PS1-1

Which of the following is a chemical reaction?

• Water freezes.
• Sugar dissolves in water.
• Salt and pepper are mixed in a dish.
• Iron rusts.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Which observation would most likely indicate that an exothermic reaction has occurred?

• a color change

• the production of gas bubbles

• an increase in temperature

• a decrease in temperature

Suppose two substances were combined together in a beaker. You know that a chemical reaction occurred if:

• new substances were created.
• one substance dissolved in the other.
• one substance melted in the other.
•  the two substances remained separate.

Tags

NGSS.MS-PS1-2