Balancing Chemical Equations: Guided Notes Review

What is the primary reason for balancing chemical equations?

• To obey the law of conservation of mass

• To simplify the chemical formulas

• To make them look symmetrical

• To make them easier to understand

Tags

NGSS.MS-PS1-5

What does a coefficient in a chemical equation specify?

• The speed of the reaction

• The type of chemical reaction

• The number of molecules

• The temperature at which the reaction occurs

Tags

NGSS.MS-PS1-1

What does the subscript in a chemical formula indicate?

• The number of phases

• The number of reactions

• The number of atoms of that element in the molecule

• The number of possible products

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NGSS.MS-PS1-1

What does the arrow in a chemical equation signify?

• The catalyst used in the reaction

• The end of the reaction

• The reactants yielding the products

• Direction of heat flow

According to the law of conservation of mass, matter is:

• Created during chemical reactions

• Destroyed during chemical reactions

• Neither created nor destroyed

• Converted into energy

Tags

NGSS.MS-PS1-5

Which of the following is NOT allowed when balancing chemical equations?

• Adding coefficients

• Ensuring equal mass on both sides

• Counting atoms

• Changing subscripts

What must be true for a chemical equation to be considered balanced?

• It must occur at room temperature

• It must have equal numbers and types of atoms on both sides

• It must only use gases

• It must contain water

Tags

NGSS.MS-PS1-5

In the example of balancing sodium and oxygen, what was necessary to balance the equation?

• Increase the temperature

• Add a coefficient to sodium

• Remove oxygen from the equation

• Change the subscript of sodium

Tags

NGSS.MS-PS1-5

When balancing hydrogen and oxygen to form water, what was adjusted?

• The subscript of oxygen

• The type of bonds in water

• The physical state of water

• The coefficient of hydrogen

Tags

NGSS.MS-PS1-5

What is the result of adding a coefficient in front of a molecule in a chemical equation?

• It alters the chemical properties

• It decreases the reaction time

• It increases the number of molecules

• It changes the type of molecule