Show:
Bonding
Periodic Table
Law of Conservation of Mass
Chemical vs Physical
Density and Melting Point
100
What causes the atoms in ionic bonds to "stick together"?
The negative ions are attracted to the positive ions.
100
Is the periodic table sorted by atomic mass or atomic number?
What is atomic number?
100
On which side of a chemical equation do you find reactants?
the left side
100
What is it called when energy is absorbed in a chemical or physical process? (hint: the absorption of thermal energy makes the substance cooler)
endothermic
100
What is the formula for density?
D = m/V
200
What causes metals to have positive charges and nonmetals to have negative charges?
Nonmetals attract electrons causing them to have negative charges. Metals give up their electrons causing them to have positive charges.
200
The number of valence electrons is equal to ___. Double the points if you can name an exception.
What is group number? (except He)
200
How do you prove that mass is conserved?
Count the number of atoms for each element on each side of the equation to make sure that they are equal.
200
Which can be physically separated: mixtures or compounds
mixtures
200
Which doesn't change based on the size of the object: density or melting point.
Neither one changes.
300
Ionic bonding occurs between a ___ and a ___.
What is metal and nonmetal?
300
Why is atomic mass a number with a decimal?
It is an average of different atomic masses for an element.
300
Which can be changed and why: subscripts or coefficients?
Coefficients can be changed because they just change the quantity of atoms or molecules. Subscripts cannot be changed because that would change the actual chemical composition (ratio of elements in a compound).
300
Chemical or physical change: boiling
physical
300
Describe one way to determine volume. Double the points if you describe two ways to determine volume.
Use a ruler to measure LxWxH. Use a graduated cylinder for water displacement.
400
Calcium (Ca) and sulfur (S) create which compound?
What is CaS?
400
If Brittonium has an atomic number of 150 and an atomic mass of 350, how many protons, neutrons, and electrons does it have (assume a neutral atom)? Double the points if you identify which particles have which charge.
150 protons (positive), 200 neutrons (neutral), 150 electrons (negative)
400
What is an open system?
A system in which matter can enter or escape
400
Name three signs of a chemical change.
odor change, color change, temperature change, formation of a gas, formation of precipitate
400
Give two units for density
g/mL and g/cm3
500
Why do metals want to get rid of their valence electrons?
So they can drop down to the next shell down which is full.
500
Elements that share a group tend to have similar properties. Why might this be?
They have the same number of valence electrons, so they have similar charges and react with similar elements.
500
If the Law of Conservation of Mass is true, then why does the mass of ash in a fireplace not equal the mass of the firewood that is put into the fire?
A fireplace is an open system. Carbon dioxide and other gases escape up the chimney.
500
Draw a diagram of heat vs temperature for water, showing the relationship between heat and temperature as H2O goes through different phase changes. Double the points if you correctly label temperatures, phases, and phase changes.
Example: https://lh4.googleusercontent.com/JsXJu-mjFPp0_5xeQrC2BJarsQ-qJHLCZ2vhSPlAIYBOjb8rh0fqkNL4YsiRaop77seP5Ewj7yBDfPAj4sBgIEfDRm4nZrKXaACkui0L4T0Trhp0AlwRNO5g
500
What is the melting point for H2O? What is the freezing point for H2O?
0 degrees celsius (32 degree F)