Give the empirical formula of each of the following compounds if a sample contains the following quantities of each element. (Type your answer using the format CO2 for CO2.)
(a) 0.0455 mol C, 0.039 mol H, and 0.013 mol O
(b) 6.44 g nitrogen and 3.67 g oxygen
(c) 69.9% iron and 30.1% oxygen by mass
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Container A holds 732 mL of ideal gas at 2.30 atm. Container B holds 114 mL of ideal gas at 4.30 atm. If the gases are allowed to mix together, what is the resulting pressure?
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1. Using a table of standard reduction potentials, standard conditions are assumed.
(a) Arrange the following chemical species: Zn(s), Cl-(aq), Cu(s), K(s), and H2(g) in order of their ease of oxidation, from easiest to oxidize to hardest to oxidize.
(b) Arrange the following chemical species: H+(aq), I2(s), Na+(aq), Ag+(aq), and H2O(l) in order of their ease of reduction, from easiest to reduce to hardest to reduce.
2. Which of the following reactions is/are product favored?
Zn(s) + I2(s) ? Zn+2 (aq) + 2I-(aq)
2Cl-(aq) + I2(s) ? Cl2(g) + 2I-(aq)
2Na+(aq) + 2Cl-(aq) ? 2Na(s) + Cl2(g)
2K(s) + 2H2O(l) ? 2K+(aq) + H2(g) + 2OH-(aq)
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Match each chemical compound below with its corresponding dominant force.
Note: The best way to approach this problem is to use the chemical name to draw the formula, and then if necessary draw the corresponding Lewis structure.
sulfur difluoride
\hydrogen bonding dispersion forces dipole-dipole ion-ion
dihydrogen dioxide
hydrogen bonding dispersion forces dipole-dipole ion-ion
sulfur trioxide
hydrogen bonding dispersion forces dipole-dipole ion-ion
sodium chloride
hydrogen bonding dispersion forces dipole-dipole ion-ion
xenon tetrafluoride
hydrogen bonding dispersion forces dipole-dipole ion-ion
hydrogen fluoride
hydrogen bonding dispersion forces dipole-dipole ion-ion
ammonium iodide
hydrogen bonding dispersion forces dipole-dipole ion-ion
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10) If a gas sample is heated, which change is expected?
a. Volume would increase.
b. Volume would decrease.
c. Volume is a fixed quantity; it cannot change.
d. The initial and final temperature does not affect volume.
11) If the pressure of a liquid was 600. mmHg, what is its pressure in torr?
12) In a gas, the particles
a. are close to each other.
b. are moving rapidly.
c. attract or repel.
d. All of these statements are true.
13) Suppose we take a 4.0 liter sample of a gas at 1.0 atm and increase the temperature from 22 C to100 C. What will the final pressure be if the volume does not change?
17) What is true about gases when the temperature increases?
a. The gas molecules collide with the walls of the container with more force.
b. The gas molecules move faster.
c. Gas particles hit the walls of the container more often.
d. All of these statements are true.
18) Which statement is incorrect when considering gases?
a. Gas molecules are not in motion at room temperature.
b. The pressure of a gas increases when the gas particles collide with the walls of the
chamber with more force.
c. A reason why molecules of a gas fill a container is that there is no attraction between the
molecules of the gas.
d. Statements 1 and 2 are both false.
19) Which statement is true?
a. When pressure increases, volume increases.
b. When temperature increases, volume increases.
c. When temperature increases, pressure decreases.
d. When the number of moles of gas increases, the pressure decreases.
20) What mass of neon has a volume of 56.0 L at STP?
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The formation constant* of [M(CN)4]2– is 7.70 × 1016, where M is a generic metal. A 0.140-mole quantity of M(NO3)2 is added to a liter of 0.890 M NaCN solution. What is the concentration of M +2 ions at equilibrium?
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Your book has a wonderful term for the coordinated control of glycolysis and gluconeogenesis: reciprocal.
One is stimulated when the other is suppressed. But not only physiological conditions have such effect -- so do individual compounds found in cells.
A key control point in the pathways are the steps catalyzed by phosphofructokinase (in glycolysis) and fructose-1,6-bisphosphatase (in gluconeogenesis). Let's zero in on this spot.
A. Identify 3 compounds that act reciprocally on these two enzymes (inhibiting one and activating the other).
B. Now, explain why the buildup of each of these, in turn, makes sense physiologically. Why, for instance, does it make sense that AMP activates phosphofructokinase and but inhibits fructose-1,6-bisphosphatase? Answer that and then answer a similar question for the other two effector molecules that you identified in part A.
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Read the following case study:
Swan is a 14-year-old student at the Sea-Cow School for the Performing Arts. Her goal in life is to be a world-acclaimed ballet dancer. She has been dancing ever since she was 4 years old, when her parents enrolled her in a Ballet for Tots program. Swan’s parents have always encouraged her to pursue her dream of dancing professionally. As a young girl, Swan had the perfect body for a ballet dancer, slim and flexible. Within the last year, Swan has become concerned that she is gaining weight. She heard from friends that smoking cigarettes could help her stay thin, although she didn’t exactly know why. Swan became desperate to control her weight and started borrowing cigarettes from friends. Eventually, she was smoking almost a pack of cigarettes a day and felt edgy and irritable if she went without smoking for more than a few hours. She thought about trying diet pills or even barbiturates to avoid the smell of the cigarette smoke.
Swan’s parents have approached you, the school counselor, because they found rolling papers in her room. Although Swan denies using any other drugs, her parents are convinced that she has been smoking marijuana. 1.) How would you approach this as case as a school counselor? 2.) Do you think Swan is at risk for addiction? 3.)What questions would you ask Swan and/or her parents? 4.)What recommendations would you make?
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Write four paragraphs (at least a page) talking about LEAD.
a. Define LEAD, the means of transportation and transformation of LEAD, the sources of LEAD and the effects it has on human beings and the enviroment.
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What massof Na2SO4 • 10H2O is needed to prepare a solution of
Na2SO4(aq)
containing 1.5 × 10^20 anions? (Be sure to indicate the appropriate
number of
significant figuresin the final answer.)
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In what ways are the fuel supply and hormonal signals similar in untreated diabetes mellitus and starvation? In what ways are they dissimilar?
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In Iodometric Analysis of Copper in Copper Oxide, why did I not need to accurately weigh out the KI used in the standard and unknown analysis?
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Under what circumstances would we want to use a solvent pair for recrystallization instead of a single solvent? What can cause 'oiling out'?
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Answer the following questions:
a. Define expansion work vs. non-expansion work.
b. Referring to the definition of the Gibbs energy (Eq. 6.9 in your text), show that dG represents the maximum amount of non-expansion work that a system can perform at constant T, and P.
c. Explain why G is referred to as a thermodynamic potential.
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9A ) A 0.1752 g sample of solid primary standard AgNO3 was dissolved in water and titrated with 21.672 g of dilute KSCN solution. Calculate the weight molarity of KSCN solution?
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