(i have a chemistry study guide that confuses me, anything will ! )

1) the variable observed during an experiment
is called
2) pure chemistry is defined as
3) if the given mass of silver is 45.6g , and the density of silver is 10.5g/ml, calculate the volume
4) an example of physical properties of a substance is
5) difference between a mixture and a compound is
6) particles found in nucleus are
7) the sum of the protons and neutrons in an atom equals the
8) the maximum number of d orbitals in a principal energy level are
9) elements that are characterized by the filling of p orbitals are classified as
10) the atomic radius ( increase/decrease) from top to bottom in a group in the periodic table
11) cations are formed by
12) compared with the electronegativities of the elements on the left side of a period, the electronegativities of the elements on the right side of the same period tend to be /higher)
13) the number of valence electrons are in a silicon atom are
14) the formula for sodium sulfate
15) the characteristic of metals that makes them good electrical conductors
16) the weakest attraction between molecules is called
17) the formula of phosphoric acid is
18) the correct name for cocl2 is
19) the empirical formula of a substance that is 53.5% c, 15.5% h, and 31.1% n by weight is
20) the percent composition of chromium in bacro4
answer the following in full sentences; show your complete work for numerical problems
1) the element chromium has four naturally occurring isotopes. use the relative abundance of each to calculate the average atomic mass of chromium.
cr=4.34%, cr=83.79%, cr=9.50% and cr=2.37%

2) write down the electron configuration for the chloride ion and sulfide ion

3) calculate the percent by mass of hydrogen in aspirin, c9h8o4

4) describe the shapes and relative energies of the s, p, d, and f atomic orbitals

5) explain how atoms (ions) are held together in an ionic bond. give an example of an ionic compound

6) a 500-g sample of al2 (so4)3 is reacted with 450 g of ca (oh)2. a total of 596 g of caso4 is produced. what is the limiting reagent in this reaction, and how many moles of excess reagent are unreacted? ( full credit will be given for this question as this topic was skipped)

7) predict the precipitate that forms when aqueous solutions of silver nitrate and potassium chloride react to form products in a double-replacement reaction. include a discussion of how to write the complete chemical equation describing this reaction.

8) compare and contrast dalton’s atomic theory with jj thompson’s plum pudding model.

9) how many liters of o2 are needed to react completely with 45.0 l of h2s at stp?

10) the diameter of a carbon atom is 0.154 m. what is this number expressed in scientific notation?
11) explain what is meant by vsepr theory. give an example of how vsepr theory can be applied to predict the shape of a molecule.
12) what is the quantum mechanical model?