Which of the following changes demonstrates a physical change?
Ice cube melting
Burning a log
Rust on a metal shovel
Baking Bread
Ice Cube melting
What is density?
The amount of matter in a given volume.
Which of the follow describes a physical change.
A: a marshmallow burns over an open flame.
B: icicles melt from a rooftop.
C: A cat eats a piece of fish.
D: Milk turns sour.
B: Icicles melt from a rooftop.
Open book to page 36:
Based on the data and the first two models, which atom is represented by the red clay?
Chlorine
The number of teeth an adult human has.
32
Which of the following changes demonstrates a chemical property?
substance breaks in half
substance combusts
hammer bounces off substance
substance floats in water
substance combusts
d = m/v
Which of the following describes a chemical change?
A: Clear liquid mix, produces a cloudy liquid with yellow chunks.
B: Silver coins are melted down and shaped into a solid brick.
C: Salt is added to a pot of hot water and the water's boiling point changes.
D: An apple is chopped into eight slices.
A
Which of the following can be done using the studnets' models. Select all that apply:
A: Visualize the atoms bonded within the molecule.
B: Determine the thermal energy of a hydrogen chloride atom.
C: Show that some molecules are not compounds.
D: Demonstrate how elements can combine to form different types of matter.
A, B and D
How long does a human red blood cell survive?
120 days
Which of the following is a solution?
salt water
macaroni and cheese
cake mix
vegetable soup
salt water
What is the density of an object whose mass is 180 grams and whose volume is 45 cm^3
4 g/cm^3
The law of conservation of mass states that:
A: Matter is neither created or destroyed
B: the mass of an object remains the same even if chemical changes occur.
C: The number of molecules before and after a chemical reaction cannot change.
D: Mass is lost when a chemical change occurs.
A
How does the hydrogen molecule differ from the other molecules?
Hydrogen is the only one that is not a compound, it is made up of only one type of atom.
Where can you find the smallest bone in the human body?
The inner ear.
The abilities to dissolve in water and to conduct electricity are examples of:
natural properties
chemical properties
natural laws of matter
physical properties
physical properties
Weight is a flawed measure of mass because
A: is not used in other countries.
B: is affected by the force of gravity.
C: tends to fluctuate.
D: can be influenced by temperature and pressure.
Temperature is:
A: The movement of thermal energy from a solid to a liquid.
B: The difference in thermal energy between two objects.
C: a measure of how hot or cold something is.
D:a measure of how fast thermal energy is moving.
C
Which model has been constructed incorrectly. How would you fix it?
The third model, It should have three hydrogen atoms.
Can you hear anything in outer space?
no
Which of the following is a substance:
table salt
sea water
sand
You must explain!
table salt is a substance. It always has the same composition and properties. Seawater composition can vary as can sand.
Describe two ways to measure the volume of a solid object.
LxWxH
If it is irregular, it can be placed into a known volume of water and the total volume can be measured with the object immersed. The difference is the volume.
______ and _______ are two types of energy that can be released when something burns.
Thermal and light
Review the chart to determine which atoms are needed to model nitrogen trichloride. Describe how you would build the model, including which colors of clay you would use.
one blue and three red balls connected with pipe cleaners. The blue ball is in the middle.
Where is the world's most active volcano located?
Hawaii