CFA 2.5: Chemical Equations & Reactions Corrections

Balance the following:

____ Fe + ____ Cl₂ → ____ FeCl₃

• 1,1,2
• 1,3,1
• 2,2,3
• 2,3,2

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The number of atoms you begin with in a chemical reaction ...

• must be the same as the number of  atoms you end with
• must be an even number
• can be different to the number you finish with
• changes depending on how much energy is formed

Tags

NGSS.MS-PS1-5

Balancing the following:

____ Al + ____ HCl → ____ AlCl₃ + ____ H₂

• 1,3,1,2
• 2,3,2,3
• 2,6,2,3
• 3,2,6,2

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The Law of Conservation of Matter states that the total mass of the reactants should be 

• More than the mass of the products
• Equal to the mass of the products
• Ignored during the reaction
• Less than the mass of the products

Tags

NGSS.MS-PS1-5

When balancing equations, the rule is that you can only add, change, and remove

• Coefficients
• Mass
• Subscripts
• Elements 

In a chemical reaction, if the reactants are heated, the reaction usually happens

• slower

• faster

• at the same rate

• in a smaller volume

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which of the following is a common sign that a chemical change has occurred?

• A chemical has turned a different color, bubbled, and/or changed temperature.

• A chemical has changed to a different state of matter, such as a liquid to a solid.

• A chemical has changed size.

• A chemical has become a different shape.

Tags

NGSS.MS-PS1-2

the starting materials in a chemical reaction

• Products
• Reactants
• Starters
• Enders

Tags

NGSS.MS-PS1-5

a substance that is formed as the result of a chemical reaction

• Product 
• Reactant
• Starters
• Enders

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

In an exothermic reaction, heat is ...

• taken in
• given out

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5