Chemical Change
What is a Chemical Change?
A reaction with 2 or more substances to create a completely new substance
Is adding food coloring to water a physical change? true or false
true
Is the combination of Milk and Vinegar a chemical reaction?
The symbolic representation of a chemical reaction in the form of symbols and formulas.
What do plants use as food?
Is burning wood a physical or a chemical change?
A chemical Change
What is physical change?
A change in a substance including caracteristics such as shape, size, volume, color, texture, density and mass.
What is a chemical reaction?
A process in which one or more substances, also called reactants, are converted to one or more different substances, known as products.
Is this equation balanced or unbalanced:
4Al + 3O2 →2Al2O3
balanced
Al= 4 Al= 4
O = 6 O= 6
What is needed to create glucose in photosynthesis?
Carbon Dioxide and Water
What are the 5 pieces of evidence that prove a chemical reaction?
Gas bubbles are formed, A precipitate is created, Temperature changes, Color Changes and an odor is formed
If a pan starts to rust is it a physical or chemical change?
A liquid substance turned into a solid when mixed with another liquid substance, what chemical reaction did it have?
A precipitate (a solid) was formed
What is the law of conservation of mass?
Mass that cannot be created nor destroyed
Why are plants the only ones who can create their own food?
Because they are the only being who have things called chloroplasts, which creates their food.
What is NOT a chemical change?
Freezing water / Ice
Is changes in shape and size an example of a physical or chemical change In matter?
Physical
The substances at the beginning of a chemical equation are called the _____
Reactants
Is this a balanced or unbalanced chemical equation?
2C2H6 + 7O2 —> 6H2O + 4CO2
unbalanced
C= 4 C= 4
H= 12 H= 12
O= 14 O= 9
What does the chlorophyll in plants do?
They trap sunlight to start the photosynthesis process, and add the green pigment to leaves.
What chemical and physical changes occur when a candle is lit?
Chemical change: The candle wick turns into ash, creating gas, smoke, and heat.
Physical change: The wax melts, becoming a liquid, then it freezes, turning into a solid again
What is the difference between a physical and chemical change?
What is the coefficient in a chemical reaction?
Its the number of molecules in a chemical reaction
What is the difference between balanced and unbalanced chemical equations?
Balanced equations have the same number of atoms, while unbalanced equations have different numbers of atoms in both sides.
What are Autotophs?
The autotrophs are the ones who can create their own food, meaning they create their own nutrients and energy.