Properties
Name all six properties
1) Thermal Conductivity
2) Hardness
3) Solubility
4) Electrical Conductivity
5) Magnetism
6) Reflectivity
What is the difference between physical and chemical change?
Chemical changes create new substances, but physical changes do not
True or False
When two substances are combined, a new substance is always formed.
False
True or False
This sentence is written in the passive voice
I placed the salt into the rubbing alcohol and it dissolved.
The salt was mixed with the rubbing alcohol and dissolved.
What is the difference between closed and open systems?
Closed systems- nothing can get out or in
Open systems- anything can get in or out
Tyrone has two different nails. He wants to figure out which one is metal and plastic.
Name all properties Tyrone can test for
Magnetism
Reflectivity
Thermal Conductivity
Hardness
Electrical Conductivity
True or False
A physical change can often be reversed, but a chemical change cannot.
True
What are the six ways that proves a new substance was made?
-Color change
-Temperature change
-Property change
-Irreversible change
-Solid formation
-Gas production
How do you know a sentence is written in the passive voice?
The sentence includes:
-"was" next to the verb
-Not in 1st person
KB is trying to make elephant toothpaste. He starts to mix the ingredients but nothing is happening.
(1pt) What is this called in an experiment?
(1pt) Name one example
-Too much or too little of the ingredients
- Did not mix enough
True or False
All substances have the same properties
False
Why can’t most chemical changes be reversed?
a) Because new substances are formed.
b) Because the original materials are gone forever.
c) Because they don’t create anything new.
a) because new substance are formed
Paris is mixing baking soda, phenol red, and calcium chloride.
Was a new substance made? Why or why not?
When phenol red mixed with calcium chloride and baking soda, a new substance was made.
-Color change from red to bright orange
-Temperature increase
-Bubbles started to form
-Irreversible change
Rewrite this sentence in the passive voice
Hannah took the sand and put it in the water.
The sand was mixed with the water
How can mass change in an open system vs a closed system?
Open system= Mass can increase or decrease
Closed system= Mass doesn't change
Describe the test for reflectivity
To test for reflectivity, an object was shined with a flashlight. If the object shined the light back, it is reflective.
If the object does not shine light back, it is non-reflective.
True or False
Ice melting is a chemical change
False
Ice melting is a physical change
The water molecules do not change
Dominic and Isabella decide to make elephant toothpaste. They gathered all the ingredients and followed the procedure.
Is a new substance being made when mixing the ingredients for elephant toothpaste?
When making elephant toothpaste, a new substance is being made.
First piece of evidence is the color changing from white to blue
Another piece of evidence is irreversible change.
Final piece of evidence is gas production through bubbles forming.
Is this sentence written in the passive voice or 3rd person?
The substance is easily bent, so it is soft.
3rd person
Ferlyn found the mass of a piece of paper. The scale read 4 grams. The paper was ripped in half and placed on the scale.
What was the mass of the paper? Why?
4 grams
During a physical change, the substance does not change in mass, only in shape or size.
Brian found unlabeled two powders in the kitchen. He wants to figure out which one is salt and sugar.
(1pt) What property should he test for?
(1pt) Describe the test he should preform
Solubility
To test for solubility, a powder was mixed with water. If the powder dissolves in the water, it is soluble. If the powder does not dissolves in the water, it is insoluble.
(2 point question)
Is making a lava lamp an example of physical or chemical change? Why?
Physical change because the substances can be separated.
When mixing sulfuric acid and sugar, what are the pieces of evidence of a new substance being made?
1) Color change from white to black
2) Solid formation
3) Property change from liquid to solid
4) Irreversible change
5) Gas production through bubbles forming
Which sentences are written in 3rd person or passive voice?
Salt and water were mixed in a jar.
Calcium chloride dissolved in the water and got hot.
All metals are conductors.
When a magnet was placed next to the nail, the nail was attracted to it.
1. Passive Voice
2. 3rd person
3. 3rd person
4. Passive voice
Ms.MC found the mass of calcium chloride and water before mixing them together. The mass before the mixture was 28 grams. The calcium chloride was mixed with the water and placed on the scale. The mass after read 30 grams.
(1pt) Was the mass suppose to change?
(1pt) What are some human errors?
No, the mass was suppose to stay the same
-Not closing the baggie immediately
-Spilling
-Not zeroing the scale