Chemical Changes
A student mixed vinegar and baking soda. Bubbles formed this is an example of...
Production of gas/chemical change/formation of a new substance
An unknown substance has a density of 1.4 g/cm3. What could this substance be?
Quartz- 1.2g/cm3
Iron- 2.9 g/cm3
Steel- 4.1 g/cm3
Aluminum- 1.4 g/cm3
Aluminum
An object has a mass of 50g and a volume of 25cm3. What is it's density?
2 g/cm3
A student placed 100mL of water into a graduated cylinder. He then placed an unknown rock in the cylinder and the water rose to 120mL. What is the volume?
20mL
The amount of space an object takes up
volume
students were conducting a lab looking for evidence of chemical changes. They mixed to substances into a ziplock bag, and observed that the bag filled up with gas. Did a chemical change occur? How to do you know?
An unknown substance has a volume of 5 mL and a mass of about 100 g. What could this substance be?
Copper- 8.92
Water- 1.00
Gold- 19.83
Calcium- 1.55
Gold
An object has a mass of 50g and a volume of 60 g/cm3. Will it float in water?
No
A student placed a coin in a graduated cylinder with 25 mL. The water rose to 25.5 mL. What is the volume of the coin?
0.5 mL
the amount of matter in an object
mass
Baking a cake is an example of a chemical change. Name two pieces of evidence that prove this.
Answers will vary.
Substance 1 has a volume of 20cm3 and a mass of 60g
Substance 2 has a volume of 40 cm3 and a mass of 60g.
Which substance has the HIGHEST density
Substance 2
An object has a mass of .5 g and a volume of 8 mL. what is it's density?
0.0625 g/mL
A cube has a length of 3 cm, a width of 5 cm, and a height of 4 cm. What is the volume?
60cm3
Chemical Change
Explain what a precipitate is. Why is this evidence that a chemical change occurred?
Solid that forms after mixing 2 liquids. A new substance is formed.
Substance 1 - mass 10 g. Volume 5mL
Substance 2- mass 185 g. Volume 150 mL
Which Substance has the LOWEST density?
Substance 2
An rock has a mass of 50 grams. When students placed the rock in a graduated cylinder with 100 mL of water in it, the water rose 25mL. What is the density of the rock?
2 g/mL
A box has a height of 12 cm, a width of 10 cm, and a length of 6 cm. What is the volume?
720 cm3
a change that does NOT create a new substance
physical change
Name 4 pieces of evidence that could be used to determine if a chemical change has occurred.
Change in color
Change in temperature
Formation of Gas
Formation of Precipitate
*Change in odor is also acceptable*
A student found that the density of an unknown substance is 1.83 g/mL.
Which substance could it be?
Wood- 0.7 g/mL
Corn Oil- 0.92 g/mL
Water 1.0 g/mL
Corn Syrup 1.83 g/mL
Corn Syrup
A student had a graduated cylinder with 30 mL of water. He dropped a crayon with a mass of 30 grams into the water. The water rose to 36 mL. What is the density of the crayon?
5 g/mL
A student had a graduated cylinder with 125.5 mL of water in it. When he placed a toy inside of it, it rose to 156.87 mL. What is the volume?
31.37mL
The amount of mass in a given amount of space
density