ATOM AND EVE MOLES AND STOICH CHEMICAL REACTIONS SOLUTIONS AND SOLUBILITY ANYTHING

Draw the Bohr model for Sulfur (S) 1-1

2 electrons on inner shell, 8 electrons on middle, 6 electrons on outermost shell

1.Put the following elements in order from smallest atomic radius to largest: C, F, N, O 2.Put the following elements in order from least electronegativity to greatest electronegativity 1-2

F, O, N, C C, N, O, F

Which compound contains both ionic and covalent bonds? CCl 4 MgSO 4 H 2 O CO 2 1-3

MgSO 4 contains both ionic and covalent bonds

1-4 Write out the alpha decay of 207 Pb

207 Pb -> 203 Hg + 4He

1-5 A sample of element X contains 90% X-35 atoms, 8% X-37 atoms and the remainder is X- 38 atoms. What is its average atomic mass?

% X-35: 0.90 x 35 = % X-37: 0.08 x 37 = % X-38: 0.02 x 38 = 0.76

2-1 How many molecules are there in 3.33L of gas at STP?

8.9 x 10 22

2-2 2 C 2 H O 2  4 CO H 2 O a.Determine the molecules of water produced if 5.49 grams of C 2 H 2 are reacted b.What type of reaction is this?

Combustion

2-3 Aluminum reacts with fluorine gas to produce aluminum fluoride. If moles of fluorine gas react, calculate the number of moles of aluminum fluoride that will be produced. (Hint: write balanced chemical equation first!)

2 Al + 3 F 2  2 AlF 3

2-4 Lead (II) sulfide reacts with oxygen gas to produce lead (II) oxide and sulfur dioxide. If moles of O 2 were consumed using this chemical reaction, how many grams of lead(II) oxide would be produced?

119.5 grams PbS

2-5 What is the density (in g/mL) of CO 2 at STP?

g/mL

3-1 What are two differences in the physical properties between ionic compounds and molecular compounds? (think melting points, ability to conduct electricity, etc.)

Molecular compounds are not able to conduct electricity and have low melting points, ionic compounds conduct electricity when molten or dissolved and have high melting points

3-2 Which is a unique characteristic of the bonding between metal atoms? A. atoms require additional electrons to reach a stable octet. B. Atoms must give away electrons to reach a stable octet. C. Atoms share valence electrons only with neighboring atoms to reach a stable octet. D. delocalized electrons move among many atoms creating a sea of electrons.

D. Delocalized electrons move among many atoms creating a sea of electrons

3-3 Which best explains why cations are smaller than the atoms which they are formed? a.The Metallic atom gains electrons, causing a larger effective nuclear pull. b. The metallic atom loses electrons resulting in the loss of an entire energy level. c. The nonmetallic atom gains electrons, causing a larger effective nuclear pull. D. The nonmetallic atom loses electrons, resulting the loss of an entire energy level.

b. The metallic atom loses electrons resulting in the loss of an entire energy level.

3-4 How many grams of ice will melt at 0C if the ice absorbs 420. kJ of energy?

1,257 g

3-5 a.Determine if the following double replacement will occur. b.If so, predict the products and balance the reaction CaCO 3 + Al 2 (SO 4 ) 3 

a. Yes b. 3CaCO 3 + Al 2 (SO 4 ) 3  3CaSO 4 + Al 2 (CO 3 ) 3

4-1 A student performs an experiment to find the solubility of a substance. The student finds the amount of substance needed to make a saturated solution in 100 g of water at different temperatures. The student’s data are shown in the table below the graph. What is the Formula of the substance? Trial Temperature (  C) of Water g of salt in 100 g H 2 O

KClO 3

4-2 Assume that a solubility curve for a gas such as ammonia, at one atmosphere of pressure, was plotted on the solubility curve graph. Reading from left to right, would this curve would _____ a.slope upwardb. slope downward c. go straight across

Slope downward

4-3 Identify the following compounds as an Acid or Base based on its composition or given pH. 1) ___________ HF 2) _________________MgOH 3) ____Diet Coke Soda (pH = 4) 4) _______Sour Candy (pH = 4) 5) ________________HBr 6) _________________NaOH 7) ___________Tylenol (pH = 9)

1) _______acid_____ HF 2) _______base_____MgOH 3) __acid___Diet Coke Soda (pH = 4) 4) ____acid___Sour Candy (pH = 4) 5) ______acid_____HBr 6) ________base_____ NaOH 7) ____base____Tylenol (pH = 9)

4-4 What is the pH of a solution of KOH with a hydroxide concentration of [OH - ] = 1 x M?

pH = 9

4-5 A.5 M solution of KOH occupies a volume of 5 mL. How many mL must be added to dilute the solution to.3 M?

3.33 mL

5-1 What is the percent composition of bromine in aluminum bromide?

89.9%

5-2 If a unknown compound exists as 88.88% oxygen and 11.11% hydrogen, what is the molecular formula of a compound with a molar mass of 144g/mol?.

H16O8

5-3 A water sample was found to have a pH of 6. What is the hydroxide concentration in the water sample?

1 x 10 -8

5-4 If I add 100 mL of water to 20 mL of a 5M solution, what is the new concentration of the solution?

.83 M

5-5 A student believes that if they add the metal calcium to aqueous aluminum chloride, a single replacement reaction will occur. Is the student correct? If so, write and balance the complete chemical reaction that will take place.

3Ca + 2AlCl 3  2Al + 3CaCl 2