Consider the following reaction occurring at 298 K: N2O(g)+NO2(g)⇌3NO(g) Part A Show that the reaction is not spontaneous under standard conditions by calculating ΔG∘rxn.
Part B If a reaction mixture contains only N2O and NO2 at partial pressures of 1.0 atm each, the reaction will be spontaneous until some NO forms in the mixture. What maximum partial pressure of NO builds up before the reaction ceases to be spontaneous?
Part C What temperature is required to make the reaction spontaneous under standard conditions?
In: Chemistry
Suppose you have 1.00 L of an aqueous buffer containing 60.0 mmol benzoic acid (pKa = 4.20) and 40.0 mmol benzoate. Calculate the pH of this buffer.
What volume of 5.00 M NaOH would be required to increase the pH to 4.93?
In: Chemistry
George was happy he did so well on his math test after doing poorly on the last one. He knew he had the ability, but just didn’t study last time. This time he felt confident in his ability and his practice of the material. When it comes to math George has developed a:
| a. |
Social comparison. |
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| b. |
Mastery-oriented attribution. |
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| c. |
Learned helplessness attribution. |
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| d. |
Gender stereotyped expectation. |
5 points
Question 7
By middle childhood, children who hold flexible beliefs about what boys and girls can do:
| a. |
Are more likely to be androgynous. |
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| b. |
Are more likely to notice instances of gender discrimination. |
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| c. |
Get more encouragement from teachers to participate in gender-typed activities. |
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| d. |
Show more in-group favoritism. |
5 points
Question 8
One factor that can reduce performance on intelligence tests is a child’s anxiety about being negatively judged based on a preconceived expectation of performance for his or her race, culture, or gender, also known as:
| a. |
Stereotype threat. |
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| b. |
Knowledge threat. |
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| c. |
Judgment threat. |
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| d. |
Nature threat. |
5 points
Question 9
The most common psychological problem experienced by adolescents is:
| a. |
Suicidal ideation. |
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| b. |
Anxiety. |
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| c. |
Eating disorders. |
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| d. |
Depression. |
5 points
Question 10
Sternberg identified three types of intelligence that work together in various ways, depending on the task at hand. He describe these three types as:
| a. |
Logical, spatial, and kinesthetic. |
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| b. |
Mathematical, linguistic, and common sense. |
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| c. |
Analytical, creative, and linguistic. |
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| d. |
Analytical, creative, and practical. |
5 points
Question 11
A contributor to obesity in early childhood is:
| a. |
Heredity. |
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| b. |
Lack of knowledge about proper nutrition. |
|
| c. |
Family stress. |
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| d. |
All of the above. |
5 points
Question 12
Research has identified some advantages and disadvantages of being an only child. Overall, only children report:
| a. |
Higher self-esteem as compared to children with siblings. |
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| b. |
Higher self-rated personality traits. |
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| c. |
Better ability to negotiate conflict with peers. |
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| d. |
All of the above. |
5 points
Question 13
The families of chronically delinquent youth are more often characterized as:
| a. |
Low in warmth. |
|
| b. |
High in conflict. |
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| c. |
Use harsh and inconsistent discipline with low monitoring. |
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| d. |
All of the above. |
5 points
Question 14
Effective sex education programs have been shown to delay the age of initiation of sex, and to reduce the frequency of sex and the number of sexual partners. Berk (2014) lists effective elements for sex education programs. Which of the following is NOT considered an effective element of sex education:
| a. |
Parents should avoid or delay talking with their children about sex. |
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| b. |
Role-playing techniques for handling potential sexual situations, such as pressure from a date. |
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| c. |
Clear, accurate messages based on an adolescent’s culture and experience. |
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| d. |
Specific and accurate information about contraceptives. |
5 points
Question 15
Adolescents who are actively involved in a religious community tend to _______________ their peers who are not involved in religious activities.
| a. |
Score higher in empathy and prosocial behavior as compared to. |
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| b. |
To show no significant differences from. |
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| c. |
Score lower in empathy and prosocial behavior as compared to. |
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| d. |
Report a more fragile sense of moral identity as compared to. |
5 points
Question 16
Although no one was nearby, Eric tells his mother that she is embarrassing him when she asks about his homework on the way to the car. He checks his hair in the mirror when he gets in the car and worries that someone will see that his hair is out of place. Eric is concerned with:
| a. |
His mother’s inappropriate behavior. |
|
| b. |
An imaginary audience. |
|
| c. |
A personal fable. |
|
| d. |
Idealism. |
5 points
Question 17
According to the U.S. Census Bureau, the industrialized country with the highest divorce rate is:
| a. |
The United Kingdom. |
|
| b. |
The United States. |
|
| c. |
Sweden. |
|
| d. |
Canada. |
5 points
Question 18
Olivia is preparing for a Friday test of vocabulary words. On Wednesday, Olivia checks her progress on learning the vocabulary words. She is pleased with how well she has learned some of them, but is having a harder time with others. She decides to look some up on the Internet to get additional help in understanding them. She checks her progress again on Thursday. Olivia is using the process of ____________ to help her reach her goal.
| a. |
Cognitive mapping. |
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| b. |
Cognitive self-regulation. |
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| c. |
Whole language approach. |
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| d. |
Phonics approach. |
5 points
Question 19
Which of the following about children from divorced parents is NOT accurate?
| a. |
Children of high conflict families tend to transition better to a single parent home following divorce. |
|
| b. |
Children of low conflict families tend transition better to a single parent home following divorce. |
|
| c. |
Children adjust better when parents are able to coparent cooperatively following divorce. |
|
| d. |
Children adjust better when they have frequent and warm contact with the noncustodial parent. |
5 points
Question 20
As they are developing identities, many adolescents from immigrant cultures experience a clash, or ______________ due to conflicting pressures between family values and the host culture.
| a. |
Identity domains. |
|
| b. |
Acculturation stress. |
|
| c. |
Cultural bias. |
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| d. |
Identity status. |
In: Chemistry
Consider the following reaction:
I2(g)+Cl2(g)⇌2ICl(g)
Kp= 81.9 at 25 ∘C.
Calculate ΔGrxn for the reaction at 25 ∘C under each of
the following conditions.
PICl= 2.65 atm ;
PI2= 0.325 atm ;
PCl2= 0.212 atm .
In: Chemistry
Traditional solder is a low melting point alloy of lead and tin. (Some countries havemandated the future use of lead-free solders, because of concerns relating to theenvironmental consequences of lead use and disposal.) Using appropriate data gleaned from the textbook, explain
(i) why lead has very limited solubility in solid tin (hardly any lead will dissolve in tin at room temperature);
(ii) why tin is moderately soluble in solid lead (approximately 3.5% of the atoms in lead can be replaced by tin at room temperature).
In: Chemistry
How much ice (in grams) would have to melt to lower the temperature of 355 mL of water from 26 ∘C to 6 ∘C? (You must consider the enthalpy in cooling the water, as well as the enthalpy in melting the ice and the enthalpy to heat the melted ice from 0∘C up to the system's final temperature of 6 ∘C. Also assume that the density of water is 1.0 g/mL.) Express your answer using two significant figures.
In: Chemistry
What functional groups are in a receptor? Does the benzene ring in a drug or adrenaline form a hydrophobic interaction in a receptor?
In: Chemistry
Two kg of water exist initially as a vapor and liquid at 90°C in
a rigid container of volume 2.42 m3.
(a)At what pressure is the system?
(b)What is the quality of the system?
(c)The temperature of the container is raised to 100°C. What is the
quality of the system, and what is the pressure? What are ΔH and ΔU
at this point relative to the initial state?
(d)As the temperature is increased, at what temperature and
pressure does the container contain only saturated vapor? What is
ΔH and ΔU at this point relative to the initial state?
(e)Make a qualitative sketch of parts (a) through (d) on a P-V
diagram, showing the phase envelope.
In: Chemistry
How much heat energy, in kilojoules, is required to convert 32.0 g of ice at −18.0 ∘C to water at 25.0 ∘C ? Express your answer to three significant figures and include the appropriate units.
How long would it take for 1.50 mol of water at 100.0 ∘C to be converted completely into steam if heat were added at a constant rate of 25.0 J/s ?
Express your answer to three significant figures and include the appropriate units.
In: Chemistry
A student was given an old tablet of vitamin C weighed 1.022 g to analyze. The tablet was dissolved in 700.0 mL water, and 35.0 mL aliquot of this solution required 45.6 mL of unknown molarity I2 (stock A) solution to oxidize it. In another experiment, the student titrated 50. mL of that same I2 (stock A) with 17.6 mL of 0.0100 M ascorbic acid. Calculate the mg vitamin C in the tablet.
In: Chemistry
Clausius inequality: working with a cycic path shown and using his own result, clausius concluded that in an isolated system entropy increases . Can you prove the same as well?
In: Chemistry
Determine the empirical and molecular formulas of each of the following substances
Part A
Ibuprofen, a headache remedy, contains 75.69% C, 8.80% H, and 15.51% O by mass, and has a molar mass of 206 g/mol.
Express your answers as chemical formulas separated by a comma.
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Part B
Cadaverine, a foul smelling substance produced by the action of bacteria on meat, contains 58.55% C, 13.81% H, and 27.40% N by mass; its molar mass is 102.2 g/mol.
Express your answers as chemical formulas separated by a comma.
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Part C
Epinephrine (adrenaline), a hormone secreted into the bloodstream in times of danger or stress, contains 59.0%C, 7.1% H, 26.2% O, and 7.7% N by mass; its MW is about 180 amu.
Express your answers as chemical formulas separated by a comma.
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In: Chemistry
1) 1. How many ATOMS of
sulfur are present in 4.30 moles
of sulfur dioxide ?
atoms of sulfur.
2. How many MOLES of
oxygen are present in
1.91×1022 molecules of sulfur
dioxide ?
moles of oxygen.
2) 1. How many MOLECULES of
carbon tetrafluoride are present in
1.45 moles of this compound ?
molecules.
2. How many MOLES of
carbon tetrafluoride are present in
1.07×1023 molecules of this compound
?
moles.
3) 1. How many MOLECULES of
phosphorus triiodide are present in
2.80 moles of this compound ?
molecules.
2. How many MOLES of
phosphorus triiodide are present in
1.08×1023molecules of this compound
?
moles.
3) 1. How many ATOMS of
sulfur are present in 8.41 grams
of sulfur dioxide? atoms of
sulfur .
2. How many GRAMS of
oxygen are present in
1.91×1022 molecules of sulfur
dioxide ? grams of oxygen
4) 1. How many
MOLECULES of carbon tetrafluoride
are present in 1.91 grams of this compound
? molecules.
2. How many GRAMS of
carbon tetrafluoride are present in
1.07×1023 molecules of this compound
? grams.
5) 1. How many MOLECULES of
phosphorus triiodide are present in
4.98 grams of this compound
? molecules.
2. How many GRAMS of
phosphorus triiodide are present in
1.08×1023molecules of this compound
? grams.
6)
What is the mass of a sulfur dioxide molecule
?
grams
7)What is the mass of a carbon tetrafluoride
molecule ?
grams
8)What is the mass of a phosphorus triiodide
molecule ?
grams
9)1. How many GRAMS of
sulfur are present in 4.30 grams
of sulfur dioxide ?
grams sulfur.
2. How many GRAMS of
sulfur dioxide can be produced from
1.69 grams ofoxygen ?
grams sulfur dioxide.
10)1. How many GRAMS of
cobalt(II) are present in 1.36
grams of cobalt(II) sulfite ?
grams cobalt(II).
2. How many GRAMS of
cobalt(II) sulfite can be made from
4.90 grams ofcobalt(II) ?
grams cobalt(II) sulfite.
11)1. How many GRAMS of
chromium(II) are present in 2.74
grams ofchromium(II) chloride ?
grams chromium(II).
2. How many GRAMS of
chromium(II) chloride can be made from
4.92 grams ofchromium(II) ?
grams chromium(II) chloride.
In: Chemistry
|
(a) when 1/2N2(g)+3/2H2(g)?NH3(g) for NH3(g) find the value of ?H?f. |
|
(b) when S(s)+O2(g)?SO2(g) |
For SO2(g) find the value of ?H?f.
|
(c) when Rb(s)+12Cl2(g)+32O2(g)?RbClO3(s) |
For RbClO3(s) find the value of ?H?f.
In: Chemistry
Synthetically produced ethanol is an important industrial commodity used for various purposes, including as a solvent (especially for substances intended for human contact or consumption); in coatings, inks, and personal care products; for sterilization; and as a fuel. Industrial ethanol is a petrochemical synthesized by the hydrolysis of ethylene:
C2H4 (g) + H2O (v) <=>C2H5OH (v)
Some of the product is converted to diethyl ether in the undesired
side reaction:
2 C2H5OH (v)<=> (C2H5 )2O (v) + H2O (v)
The combined feed to the reactor contains 53.7 mole% C2H4, 36.7% H2O, and the balance nitrogen, and enters the reactor at 310oC. The reactor operates isothermally at 310oC. An ethylene conversion of 5% is achieved, and the yield of ethanol (moles ethanol produced/moles ethylene consumed) is 0.900. Hint: treat the reactor as an open system.
Data for Diethyl Ether:
ˆ
H of = -271.2 kJ/mol for the liquid
ˆ
Hv = 26.05 kJ/mol (assume independent of T )
Cp[kJ/(molC)] = 0.08945 + 40.33*10-5T(C) -2.244*10-7T2
(a) Calculate the reactor heating or cooling requirement in
kJ/mol feed.
(b) Why would the reactor be designed to yield such a low
conversion of ethylene? What processing
step (or steps) would probably follow the reactor in a commercial implementation of this process?
In: Chemistry