Final Jeopardy!

Naming

100

What's the chemical formula for cobalt(II) nitrate

Co(NO3)2

200

What's the name of this compound?

Sr(C₂H₃O₂)₂

strontium acetate

300

What's the name of this compound?

Mg₃N₂

magnesium nitride

400

What's the formula for sulfurous acid?

H2SO3

500

Name this compound HNCO

Cyanic acid

(NCO is the cyanATE ion. plus H makes it an acid. -ate -> -ic acid)

[stuff]

100

You are given a 0.175m solution of aqueous KF. The label on the bottle says they added exactly 347g of water to create the solution, but the grams of KF added has been smudged off. Because of your classmate's negligence you won't get an A unless you specify exactly how much KF is in the solution! Calculate the amount of KF in grams added to the solution.

m = mol solute/kg solvent

.175m = x mol KF/0.347kg H2O = .0607mol KF (58.0967g KF/1mol KF) = 3.53g KF

200

If it requires 54mL of .10M NaOH to neutralize 125mL of HCl solution, what is the concentration of the HCl solution?

NaOH + HCl -> H2O + NaCl

54mL = .054L, 125mL HCl = .125 L HCl

.10mol NaOH/1L NaOH (.054L NaOH) = .0054mol NaOH

.0054mol NaOH (1mol HCl/1mol NaOH) (1/0.125L HCl) = .0432M HCl

300

If the human eye has an osmotic pressure of 8.00 atm at 25^oC, what concentration of NaCl will provide an isotonic eye drop solution (note: solutions that are isotonic have equal osmotic pressure)

Pi = MRT

*25 degrees C = 298.15K

8 = M(.0206)(298.15K)

400

A sample of ore contains 5.95g of silver per ton of ore. What is the concentration of silver in this ore in ppm? 

ppm = mass solute/mass solution x factor of 10^6

1 ton (2000lbs/1ton) (453.59g/1lbs) = 90,718g

ppm = 5.95g silver/90,718g x 10^6 = 6.56 ppm

500

What mass of NaCl is contained in 94.88g of a 15.00% by mass solution of NaCl in water?

Percent mass = mass solute/mass solution

(Rearranged/Reworded) Mass NaCl = Mass solution x Percent NaCl as a decimal

= 94.88 g (.15)

= 14.23g NaCl

Math

100

Calculate the mass of 500mL of ethanol (in kg) if you know the density of ethanol to be 0.798g/cm³

m = (.798g/cm^3)(500) = 399g = 0.399kg

200

Surprise! I hate math and didn't want to write another question-- you have plenty already :/

Tell me one weird thing about myself for 200 points. Has to actually be weird not "you have 2 cats." If answer is debatable everyone vote whether or not they think it's weird enough to qualify

Answers may vary.

300

Which of the following solutions has the highest electrical conductivity? 

A) 0.10M Al(NO₃)₃, B) 0.01M LiBr, C) 0.10M (NH₄)₂CO₃, D) they should all be equally conductive

*(Groups should vote on whether they want a hint on what highest electrical conductivity means/how to find. If vote yes ellie check ans key)

Highest electric conductivity would have the MOST IONS!

Correct ans is A) 0.10M Al(NO₃)₃, Aluminum nitrate breaks into 4 ions (1 al3+ and 3 nitrate ions). That means that A = 0.40M ions, B= 0.20M ions and C = 0.30M ions.

400

Calculate the De Broglie wavelength of an e- (m=9.11 x 10^-28g) traveling at a speed of 2.149 x 10¹⁰m/hr. Give your answer in meters with the correct # of significant figures.

lambda = h/mv

*(need to convert mass into kg and velocity into m/s)

m=9.11 x 10^-28g = 9.11x10^-31kg

2.149 x 10¹⁰m/hr (1hr/60min) (1min/60sec) = 5,969,444.44 m/s

= 6.626x10^-34 / (9.11x10^-31)(5,969,444.44) = 4341.7716

(with correct SF) = 4.34x10^3 m

500

Some rando in your lab somehow accidentally swallowed a drop of liquid oxygen, O_2(l), which has a density of 1.149g/mL. Assuming the drop has a volume of 0.050mL, what volume of gas will be produced in the rando's stomach at body temperature (37^oC) and a pressure of 1.0atm?

n= .00005mL (1mol O2/1.149mL) = .0018 mol O2

T= 37degrees C -> 310.15K

V = .0018mol(.08206)(310.15K) 

   = .046L O2 = 46mL O₂(g)

Conceptual(ish)

100

What does it mean when an atom is reduced? When it's oxidized?

it gained e-, it lost e-.

200

Which family is most metallic in character? Why?

options: alkali metals, alkali earth metals, transition metals, halogens, noble gases

It's the alkali metals! They are the furthest to the left (periodic trends) and are the MOST REACTIVE. Want to lose electrons the most!

300

Explain electron affinity and ionization energy. Explain the periodic trend of each one on one of the large whiteboards.

Electron affinity is how badly an atom "wants" to gain an e-. increases as you move to the right. Ionization is how much energy is required to remove a valence e- from an atom. This also increases to the right

400

Explain the law of definite proportions

All samples of a given compound have the same ratio of atoms and the same ratio of their masses!

500

Identify the type of reaction and determine the products of the reaction between ammonium bromide and strontium hydroxide.

products are SrBr2 and NH4OH which evolves into 2NH3 and 2H2O. (NH3 is a gas!) So, this is a GAS EVOLUTION RXN!

Random

100

Draw the Lewis Structure for sodium oxide

[Na]+ [O]2- [Na]+

(oxygen has full valence shell)

200

What are the n, l and m_l values for the 5d orbital?

n = 5, l =2, m_l=-2,-1,0,1,2

How? n = 5 because it tells us the level is 5

l=2 because d orbitals have an l value of 2 (s=0, p=1, d=2, f=3..)

ml values = +/- l

300

Write the nuclear reaction for the positron emission of O-15.

Bonus 400 points if you can name what type of radiation rays are emitted during this process.

¹⁵₈ O -> ⁰₊₁ e + ¹⁵₇ N bonus points if you knew that GAMMA rays are released during this process.

Positrons are the antiparticles of an electron! Same mass, but opposite charge. During this process a proton is converted into a NEUTRON! That's why O -> N

400

Tetracene (C₁₈H₁₂) is an orange solid powder, and is combusted accidentally in Ellie's organic chemistry lab (oops) in the presence of oxygen gas.

What is the balanced chemical equation for the combustion of tetracene? Include states of matter in your equation.

C18H12(s) + 21 O2(g) -> 18CO2(g) + 6H2O(g) 

500

On the whiteboards or a sheet of paper if there are no whiteboards near your group, write the balanced molecular AND complete ionic equations for the reaction between cesium hydroxide and nitric acid (assume both are aqueous) and use your work to identify the spectator ions in the reaction.

M: CsOH(aq) + HNO3(aq) -> H2O(l) + CsNO3 (aq)

CIE: 

Cs+(aq) + OH-(aq) + H+(aq) + NO3-(aq) -> H2O(l) + Cs+(aq) + NO3- (aq)

spectator ions were Cs+ and NO3-