Preparation for Balancing Equations

Preparation for Balancing Equations

Review these slides to refresh concepts from previous units

Chemical Compounds and Formulas

• "Compounds are two or more atoms bonded together"

• Subscripts = how many atoms of the element there are

• Changes in subscripts or element combinations = chemical reaction!

Chemical Reactions

• "Any change that results in the breaking or formation of chemical bonds"

• When compounds break down into pieces or pieces/atoms come together to form new compounds

The Law of Conservation of Mass

• "Matter can be neither created nor destroyed"

• Chemical reactions cannot result in a gain or loss of atoms

• If an atom is on one side, it's got to be on the other side too

Multiple Choice

Which of the following compounds contain TWO hydrogen atoms?

• 2 He

• H₂O

• CH₄

• 2 HgSO₄

Multiple Choice

Which of the following contains THREE sulfur atoms?

• Al₂(SO₄)₃

• B₃(SO₄)₂

• BaS

• Ca(S₃O₂)₂

Multiple Choice

Which of the following is NOT a chemical reaction?

• 2 H₂O₂ => 2 H₂O + O₂

• 2 Mg + O₂ => 2 MgO

• H₂O + CO₂ + O₂ => CO₂ + H₂O + O₂

• HCl + NaOH => H₂O + NaCl

Multiple Choice

According to the Law of Conservation of Mass...

• Matter is gained but not lost in a chemical reaction

• Atoms are sometimes gained but never lost in a chemical reaction

• Matter may be gained or lost in a chemical reaction

• Atoms cannot be gained or lost in a chemical reaction

Use Wakelet to continue the lesson

You may follow along using Google Slides (access via Wakelet) or just watch via TEAMS. You'll return to Quizizz at the end of the lesson.

Open Ended

In your own words, what do you think would be a good way to balance the following equation: N₂ + H₂ --> NH₃

Try to describe the steps you would take and then type out your best guess at the balanced equation.