Unit 2 Chemical Reactions

What Is the reactants in this chemical equation?

4NH₃+ 5O₂-----> 4NO + 6H₂O

• 4NH₃+ 6H₂O

• 4NO + 6H₂O

• 4NH₃+ 5O₂

• 4NH₃+ 4NO

How many elements are on the reactant side of the chemical equation? 4NH₃+ 5O₂-----> 4NO + 6H₂O

• 2

• 52

• 26

• 3

How many atoms are on the product side of the chemical equation?

4NH₃+ 5O₂-----> 4NO + 6H₂O

• 26

• 3

• 4

• 52

What are the products in the chemical equation?

4NH₃+ 5O₂-----> 4NO + 6H₂O

• 4NH₃+ 5O₂

• 4NO + 6H₂O

• 4NH₃+ 4NO

• 4NO + 5O₂

Does this chemical equation follow the law of conservation of mass? 4NH₃+ 5O₂-----> 4NO + 6H₂O

• Yes; The number of atoms of each element are unequal on both the reactant and product side of the chemical equation.

• Yes; The number of atoms of each element are equal on both the reactant and product side of the chemical equation.

• No; The number of atoms of each element are equal on both the reactant and product side of the chemical equation.

• No; The number of atoms of each element are unequal on both the reactant and product side of the chemical equation.

Substances that are combined and changed during a chemical reaction.

• Reactants

• Molecules

• Products

• Chemical Equations

Substance(s) resulting from a chemical reaction.

• Reactants

• Molecule

• Chemical equations

• Products

The number placed in front of a chemical formula in a chemical equation; represents the number of molecules of that substance. Example: 2H₂O

• Subscript

• Coefficient

• Exponent

• Molecule

The number written to the right and slightly below an element in a chemical formula; represents the number of atoms of an element present in a chemical formula. Example: 2H₂O

• Subscript

• Exponent

• Coefficient

• Molecule

Which is not evidence a chemical reaction has occurred?

• The formation of a precipitate

• A color change

• Physical change

• Production of a gas