Temperature
If you have a gas and want to turn it into a liquid, do you need to heat it up or cool it down?
Cool it down.
You see an object (190g, 30mL) that looks like it is made of copper. If copper has a density of 8.96g/mL, is the object copper? (Two answers)
Density = Mass/Volume
A measurement of how much matter is in an object.
Mass
N2O gas is often called "laughing gas" because it can be used to help people ignore pain that occurs during medical procedures. NO2 gas is a pollutant found in the air. Does NO2 have the same effect on people as laughing gas? Explain.
No, they do not have the same number of Nitrogen and Oxygen. Changing one thing changes the entire chemical.
Why did ancient sailors and people who lived near the ocean understand that the earth is spherical in shape?
They could see the hull of a ship traveling away from the shore would sink out of sight before the sails and vice versa when returning.
You are watching the molecules in an object move. Suddenly, they start moving faster than before. Was the object cooled down or heated up?
Heated up.
The density of air at 25C is 0.01g/mL. You let go of a 500-mL balloon whose total mass is 10 g. Will it float away or fall on the floor? (Need two answers)
Fall to floor because it has a density of 0.02
A unit of measurement produced by the mathematical combination of simpler units.
Derived Unit
Sometimes, coal can be contaiminated with a chemical whose formula is CuFeS2. How many of each atom is in a molecule of this chemical?
1 Fe
2 S
What made people think that Christopher Columbus couldn't sail around the world?
They knew how big the Earth was and thought the journey would be too long to make by ship.
Water is at a temperature of 95C. Someone tells you that's the same as 230F. Should you believe that person? Why or why not?
You should not believe them because 95c, water is a liquid. However, at 230F, it is a gas because water boils at 212F.
On the surface of the Earth, on object that weighs 1 pound has a mass of 454g. How many kilograms is that? (1000g = 1kg)
0.45kg
Energy that is exchanged because of a difference in temperature or change in phase.
Heat
The main chemical in limestone is made of one calcium (Ca) atom, one carbon (C) atom, and three oxygen (O) atoms. What is its chemical formula?
CaCO3
You see the following measurements:
1kg, 34ms, 17%, 3L, 5g/mL, and 14cm
Identify each, in the order that is given, as a measurement of mass, distance, time, volume, concertation, or density.
Mass, Time, Concentration, Volume, Density, and Distance.
Another common temperature scale used in science is the Kelvin scale. On this scale, water freezes at 273K and boils at 373K. Which is warmer: 300K or 110C?
110C is warmer. At 300K, water is above freezing but below boiling, so it is a liquid.
An adult human finger is about 20mm wide. How many meters wide is it? (1mm = 0.001m)
0.02m
The amount of a substance in a defined volume.
Concetration
78%
What is the area of a room that measure 3 meters wide and 2 meters long?
Area = (length) x (width)
6m2
A measure of the energy associated with the random motion a substance's molecules.
Temperature
A regulation fencing sword is 90cm long. If 1 inch = 2.54cm, how many inches long is it?
35.4in
Measure units defined by Great Britian in 1825
Imperial Unit
A chemical is in its liquid phase. Are its molecules closer together or farther apart compared to when it is in its gas phase? Do the atoms move around more or less when it is a liquid compared to when it is gas?
Closer
Less
What is the volume of a cube that is 12cm long, 10cm wide, and 5cm high?
Volume = (length) x (width) x (height)
600cm3