Physical Change vs. Chemical Change
Two substances are mixed together and a gas is formed. Physical or Chemical Change?
Chemical Change--> indicator is the production of a gas.
Name two indicators that a chemical reaction has occurred:
1. change in smell
2. heat
3. light
4. unexpected color change
Look for the number of __________.
Capital Letters
What is the chemical formula of this molecule?
**Mrs. Combs pull up the picture on your screen since you are too cheap to buy the paid version of Jeopardy labs :)**
H2S
Conservation of Matter states that matter cannot be created or _____________.
destroyed
Mixing salt and pepper together. Physical or Chemical Change?
Physical--> no new substance is created and the salt and pepper could be separated.
When a chemical reaction occurs what happens to the atoms of the reactant?
The bonds between the atoms break apart and regroup to form new molecules.
Elements are made up of _____ type of atoms.
One
In a chemical equation, on which side of the arrow are the products located?
Right
You start with 40 grams of water that evaporates and turns into a gas. What is the mass of the gas?
40 grams
A straight piece of wire is coiled to make a spring. Physical or Chemical Change?
Physical Change--> The coil only changes in shape, no new substance is created.
Explain your reasoning.
Yes, the bonds between the molecules broke apart and rearranged in the product, creating a new substance.
How many Aluminum (Al)atoms are in this compound?3Al2SO4
6
3 x 2 =6
According to the image, what are the reactants in this chemical equation?
**Show Image**
Carbon Dioxide and Water
Does this model support the law of conservation of matter?
Explain why or why not.
**Show Image**
No, the number of black and white atoms do not balance out on the reactant and product sides.
What are 2 indicators that fireworks are a chemical change?
Indicators are:
1. production of heat
2. light
3. smell
Salt and Water were mixed together and boiled. The data table shows properties before and after.
Did a chemical reaction take place? Explain your reasoning.
**Display Data Table 1 and 2**
No, a chemical reaction did not occur because the properties before and after boiling are the same.
Identify this model as an element or a compound--> Explain how you know.
**Mrs. Combs show the picture**
Element. Only made of 1 type of atom (all are the same color in the model)
When looking at the following equation, how many atoms of oxygen are present on the reactant side of the equation?
**Show equation**
4
10g of white powder reacts with 10g of clear liquid. The reaction bubbles and changes color producing a black liquid that has a mass of 13g. How much gas was produced?
7 grams
Reactants: 10 grams powder + 10 grams liquid=20 Products: 13 grams liquid + x gas
20= 13 +x
20-13=7
True or False: Evaporation is a chemical change.
False--> Physical change. There is only a change in phase. The water goes from a liquid to a gas, but is still H2O.
To make soap danny added coconut oil and lye together and heated them. Afterwards it made the substances of soap and glycerol.
Did a chemical reaction occur?
What is your evidence from the table?
When the coconut oil and lye were mixed together, a chemical reaction occurred to produce soap and glycerols. This is because the data shows that the melting point and density of both reactants (coconut oil and lye) and products (soap and glycerol) are different. Melting point and density are characteristic properties that are specific to a substance and if they differ it means the substances are different
How many ELEMENTS make up this compound?
CaCO3
3
There are three elements: Ca, C, and O.
**Hint: 3 capital letters.
Does this chemical formula support the law of conservation of matter?
Explain.
**Show image**
Yes, there are the same number of reactants and products.
1 Carbon
4 Hydrogen
4 Oxygen
This model DOES NOT support the law of conservation of matter. How could it be revised?
**Show model**
One purple atom needs added to the product side.