Physical or Chemical?
state of matter, color, melting point, boiling point, oror, density, and conductivity
What is Physical Properties
Identify the reactants and products of the chemical reaction
4Fe + 6H2O + 3O2 --> 4Fe(OH)3
Reactants = Fe, H2O, and O2
Products = Fe, O, and H
A process that releases heat
What is a exothermic reaction
What does The Law of Conservation of Mass state?
dissolving salt in water is a physical change.
True or false?
True
Physical or Chemical
Flammability, corrosion or rusting, oxidation, rotting
What is Chemical Properties
What is the difference between a subscript and a coefficient
A coefficient identifies the number of molecules of a substance.
A subscript identifies the number of atoms in a formula.
Is this Endothermic or Exothermic?
Energy transfers from the surroundings to the system
What is endothermic
How does the mass of the product in a chemical reaction compare to the reactants?
The mass of the products and reactants are the same in a chemical reaction.
The reactants of a chemical reaction had a mass of 59 grams. What is the mass of the products
59 grams
Calculate the density of an object that has a mass of 100 grams and a volume of 49 ml.
What is 2.04 g/ml
D=m/v
Which of the following is an example of a chemical reaction.
Mixing hot chocolate, cracking a glow stick, condensation on a glass, baking a cake
Cracking a glow stick
Baking a cake
Baking muffins is an example of a ___________ reaction
What is a endothermic reaction
How many Nitrogen atoms are in the reactants?
2NaN3 --> 2Na + 3N2
What is 6
Draw an endothermic system
Draw an exothermic system
Endo = arrows (heat energy) entering sytem
Exo = arrows (heat energy) leaves system
Is this a chemical or physical change?
What is a physical change
What is a precipitate?
What is a solid formed from a chemical reaction
What do endothermic and exothermic reactions have in common
Is the following chemical equations balanced?
2Zn + 2HCl --> ZnCl2 + H2
What is not balanced
Balance the Chemical Equation
__ NaClO3 --> __ NaCl + __ O2
_2_ NaClO3 --> _2_ NaCl + _3_ O2
List the following items by their densities from least dense to most dense.
milk - 1.03 g/ml
steel - 7.8 g/ml
coal - 1.1 g/ml
ice - 0.92 g/ml
aluminum - 2.7 g/ml
Ice
milk
coal
aluminum
steel
What is the difference between a physical change and a chemical change?
Physical changes just change the physical appearance such as the color, size, or shape. Chemical reactions change the substance into something completely new.
identify each process as ENDO or EXO
Chemical bonds form when heat is released
Fried eggs absorb heat from a pan
Water vapor in the air releases heat and condenses into rain droplets
Combustion reaction (burning) of a match gives off heat and light
1. EXO
2. ENDO
3. EXO
4. EXO
Balance the Chemical Equation
__ Fe + __ H2O --> __ Fe3O4 + __ H2
_3_ Fe + _4_ H2O --> _1_ Fe3O4 + _4_ H2
Why is making ice an exothermic process?
Water has to release energy in order for the temperature of the system to drop low enough to freeze