Physical properties can be observed or ___________ without changing what the object being observed is made of.
Measured
100
What is the most common form of matter in the universe?
Plasma
100
How do you calculate density?
Density is equal to mass over volume.
100
What is buoyancy?
Buoyancy is the upward force exerted on an object by the fluid it is in.
100
What is condensation?
Changing from a gas to a liquid.
200
What is the difference between a force and a physical property?
A force is applied to an object, while a property is a result of the arrangement of the object's atoms.
200
In order to be considered matter, an object has to pass two tests. What are these two conditions?
Made of atoms (has mass)
Takes up space (has volume)
200
Which is more dense, a steel spoon or a steel table?
They are the same density!
200
Why are weight and mass different?
Mass = how many atoms you are made of. Weight = how strong the downward pull of gravity is on those atoms. Weight depends on gravity, mass does not.
200
What is the phase change from solid to gas called? What is the reverse phase change called?
Sublimation, Deposition
300
What is an amorphous object?
A solid with a disorganized atom arrangement (they are not in a lattice or crystal pattern).
300
Define a solid in terms of atom arrangement and movement.
Atoms in a solid are closely packed and vibrate in place.
300
You drop pink, green, and yellow liquids in a beaker. The density for each is 1.4g/ml (pink), 1.7g/ml (green), and 1.2 g/ml (yellow). What is the order they will layer in from BOTTOM to TOP?
Green on the bottom, then pink, then yellow on top.
300
Steel is more dense than water. Why do steel ships float?
Buoyant force is stronger than weight due to the surface area of the ship. Also, steel ships are mostly air, which is less dense than water.
300
To change from a solid to a liquid, you need to (increase/decrease) thermal energy in order to (increase/decrease) intermolecular forces.
INCREASE, DECREASE
400
"Thermal conduction is the transfer of heat between two objects." What 3 things are missing from this definition?
Objects must be touching. Objects must be different temperatures. Heat transfers from warmer object to cooler object
400
Define a liquid in terms of thermal energy and intermolecular forces.
Intermolecular forces are only PARTIALLY overcome by thermal energy.
400
When is the rough draft of your invention essay due? In what format must it be?
MONDAY. It must be typed and PRINTED and brought to class.
400
Siddharth's backpack is dropped in a pond and displaces 3kg of water. What is the buoyant force acting on his backpack? How do you know?
3 kg! (Archimedes' Principle!)
400
What is the difference between evaporation and boiling?
Both are phase change from liquid to gas. Boiling occurs at boiling point, evaporation occurs below boiling point.
500
Why are graphite and diamonds allotropes?
They are objects made of the same TYPE of atoms but with a different ARRANGEMENT of atoms - therefore they have DIFFERENT physical properties.
500
An object has the following physical properties: It is somewhat viscous and highly compressible. It has no definite shape. It is less dense than water. What state of matter is it?
It is a fluid (either a liquid OR a solid) - there is no way to tell which from the description!
500
The mass of an liquid is 199g and the space it takes up is 17mL. What is its density? Round to the HUNDREDTHS place and include UNITS.
11.70 g/mL (SF ROUNDING!)
500
What is the difference between positive buoyancy and neutral buoyancy?
Positive buoyancy = object floats on top of fluid, weight is less than buoyant force. Neutral buoyancy = objects hovers in the middle of the fluid, weight is equal to buoyant force.
500
How can you physically change matter without changing what that matter is made of? (There are two main ways!)
Phase changing - it changes the state of matter but it doesn't change the atoms.
Changing physical properties - changing the shape, size, volume, breaking the object into pieces, etc.