MID TERM CHEMISTRY

The products of a reaction have the same ________as the reactants.

• molecule

• atoms

• subscripts

• coefficients

Chemical reactions

• create and destoy atoms

• only occurs outside living organisms

• occurs only in living organisms

• produce new substances

What does this symbol Δ above the arrow mean?

• a precipitate is form

• heat is supplied

• a calalyst is needed

• electricity is needed

Balance this equation, CaCO₃(s) → CaO(s) + CO₂(g)?

• 3,1,2

• 1,1,1

• 1,3,1

• 2,6,3

Balance this equation, AlCl₃ + NaOH → Al(OH)₃ + NaCl

• 3,1,3,1

• 1,3,3,1

• 1,1,1,3

• 1,3,1,3

Chemical equations

• give directions for naming compounds

• describe only biological changes

• describe chemical reactions

• show how to write formulas

Which side of a chemical equation is the product side?

• Left (before the yields sign)
• Right (after the yields sign)

Balance this equation
_Zn+_HCl-->_ZnCl₂ +_H₂

• 1,1,2,1
• 1,1,1,2
• 1,2,1,1
• 2,1,1,1

Balance this equation.
_Mg + _Cl₂ --> _MgCl₂

• 1, 2,1
• already balanced
• 2,1,1
• 1,1,2

How many atoms of aluminum are on each side of the following equation: 4Al + 3O₂ --> 2Al₂ O₃

• 2
• 6
• 1
• 4