two substances mixed together that look like one thing after mixing
100
atom
What is the smallest part of matter that has unique properties?
100
What is the molar mass of potassium oxide?
94 g/mol
100
What is the charge on an sulfide ion?
-2
200
Round 342,765 to 4 significant figures
342,800
200
What unit do we use to measure volume of a substance?
Usually Liters (or any metric type of liter), or cm^3
200
An expandable container of oxygen has a volume of 125 mL at a temperature of 25.0 degrees Celsius. What volume will this gas occupy at 55.0 degrees Celsius?
137.6 mL
200
What do we use a mole for?
We use a mole to measure amounts of substance. If we measure the mass equal to a mole, we know we have 6.02 x 10^23 things.
200
Which element has 15 protons and 15 electrons?
Phosphorus
300
22.0 x .014 = x
Solve for x and round to the correct number of significant figures.
0.31
300
Which separation technique would be the best one to use to separate a solid from a liquid:
-Chromatography
-Filtration
-Distillation
-Vaporization
Filtration
300
Decreasing the volume of a sealed container will cause the particles inside the container to.....
Collide more frequently, increasing the pressure.
300
A substance has a molecular formula of C8H10N4O2. What is its empirical formula?
C4H5N2O
300
In the formula for Barium Chloride, BaCl2, Barium is written first because...
It is the positive ion
400
What is the correct measurement in the picture of the graduated cylinder?
14.4 mL
400
A student studies a sample of iron, and finds it has a mass of 342.28 g and a volume of 46.05 mL. What is the density of the iron? Round your answer to the correct number of significant figures.
7.433 g/mL
400
A sample of gas occupies 3.4 L at 1.03 atm of pressure. The pressure is doubled. What is the new volume?
1.7 L
400
How many grams are in 3.50 moles of calcium chloride?
389
400
How do you write the formula for the compound Magnesium Nitrate?
Mg(NO3)2
500
If something is measured in grams, what property are you measuring?
mass
500
A student measures the mass of an aluminum rod. He measures the mass as 12.98 g. The true value for the mass of the rod is 13.20. What is his percent error?
1.67%
500
A sample of gas in a balloon occupies 5.00L at 103.2 kPa and 298 Kelvin. What will the volume of the gas be if the pressure is decreased to 76.4 kPa and the temperature is decreased to 262 Kelvin? Round your answer to the correct number of significant figures