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Calculate the energy difference for a transition in the Paschen series for a transition from the higher energy?
Calculate the energy difference for a transition in the Paschen series for a transition from the higher energy?
Calculate the energy difference for a transition in the Paschen series for a transition from the higher energy shell n=7

En=-2.179 x 10^18 / (n)2 J

Four sig figs!

Thanks in advance!
Chemistry   zme_9325   6016   Asked 10 years ago
Chemistry question on enantiomers
Chemistry question on enantiomers
So this is actually a question in my biology class but it is a question about enantiomers so I figured I'd put it in Chemistry. Anyway! So the answer is A being that A is NOT an enantiomer. I'm not understanding why it's not if D is the same thing just with CH3 instead of a H. Any help is appreciated.
Chemistry   Xabien   418   Asked 8 years ago
Discuss the distinction between a graduated pipette and a volumetric pipette. Volumetric pipettes ...
Discuss the distinction between a graduated pipette and a volumetric pipette. Volumetric pipettes ...
Discuss the distinction between a graduated pipette and a volumetric pipette. Volumetric pipettes are used to transfer one specified volume of liquid while graduated pipettes are used to transfer volumes other than specific volumes for which volumetric pipettes are calibrated.

Clarify the specific function of each and when each should be used.  Volumetric pipettes ar
Chemistry   vern   3661   Asked 12 years ago
What is a Polar Covalent Bond?
What is a Polar Covalent Bond?
A polar covalent bond is a bond between two non-metals with different electronegativities. Only bonds between the same elements are truly nonpolar. The higher the difference in electronegativity, the more polar the bond is. Take a look at this table of electronegavities and let's try some examples.

[url=http://chemistry.tutorpace.com/polar-covalent-bond-online-tutor
Chemistry   tutorpace   326   Asked 8 years ago
Chemistry for Today: General, Organic, and Biochemistry, 6th Edition Seager, Sla
Chemistry for Today: General, Organic, and Biochemistry, 6th Edition Seager, Sla
Hi does anyone have Chemistry for Today: General, Organic, and Biochemistry, 6th Edition
Seager, Slabaugh test bank questions? Please let me know ASAP
Chemistry   trisha101   2186   Asked 11 years ago
percent yield and atom economy
percent yield and atom economy
How would i go about doing q 4-7
Can someone tell me how to set up these equations and put a ? where i should plug in my lab results...attached pic with questions
Chemistry   toodaloo   438   Asked 10 years ago
IR SPECTRIUM questions
IR SPECTRIUM questions
can someone help me out - ive done these questions but not so sure of my answer
attached the two questions as a picture
would really appreciate some help thanks
Chemistry   toodaloo   655   Asked 10 years ago
Hexane boils at 156.2oF. What is this temperature in Celcius? What is this temperature in Kelvin?
Hexane boils at 156.2oF. What is this temperature in Celcius? What is this temperature in Kelvin?

Question 1 of 12
Which of the following is an example of an observation? 
 A. Reactions occur due to the transfer of electrons. 
 
 B. All matter is composed of small, indestructible particles called atoms. 
 
 C. Flammable objects contain phlogiston. 
 
 D. When a can of soda pop is opened, a f
Chemistry   TOLBERTJD   10049   Asked 11 years ago
Write the chemical formula for each of the following ionic compounds: Copper (II) Bromide, Silver (I
Write the chemical formula for each of the following ionic compounds: Copper (II) Bromide, Silver (I
Question 1 of 12
Identify the element that is a nonmetal, a gas, and has an elemental symbol that starts with the letter "A." 
 A. Al 
 
 B. Ac 
 
 C. Au 
 
 D. Ar 
 
 E. none of the above 

Answer Key: D


Question 2 of 12
Which st
Chemistry   TOLBERTJD   7072   Asked 11 years ago
Questions about Buffers and pH levels and such.....
Questions about Buffers and pH levels and such.....
Research a buffer system that interests you and report the following:
 
(A)    What is the system that is buffered?
(B)    What is the pH of the system?
(C)    What compounds are responsible for the buffered system?
(D)    What benefit does being at this pH serve?
(E)    How could this system be shifted
Chemistry   tink571937   852   Asked 12 years ago
Chemical Reactions
Chemical Reactions
Chemical reactions are happening around us all the time; the CO2 in a can of soda is at equilibrium, batteries, fuel cells, acid rain, decaffeination of coffee (why bother?), reaction of sunscreen with skin, and on and on and on. There are also a number of household chemicals that when mixed can create an explosion or other hazardous situation. Try to think of a way chemicals are re
Chemistry   tink571937   929   Asked 12 years ago
Calculting in Chemistry
Calculting in Chemistry
(A.) Calculate the cost per gram (g) of synthetic baccatin III, the Taxol precursor, using the following assumptions. Basically, what you are doing here is calculating how much it would cost to just synthesize the chemical needed to make Taxol in the laboratory, without relying on nature. Be sure to look at the attached picture (Figure 1) before trying to answer this question. You d
Chemistry   tink571937   1155   Asked 12 years ago
the calculation with buffer liquid
the calculation with buffer liquid
pH of blood is 7,4
K= (the concentration of H3O+)(the concentration of HCO3-)/(the concentration of CO2) = 4,5*10ˆ-7
How to calculate the rate of CO2/HCO3-
Chemistry   thupham   2667   Asked 9 years ago
predict the initial rate
predict the initial rate
predict the initial rate if [no]= 0.30 m and [h2]=0.15 m
what would happen to the initial rate of the reactonif[no]=0.60 m and [h2]=0.15 m instead. does your result make sense interms of order of reacton?
Post Merge: 11 years ago

anyone??
Chemistry   thains32   4302   Asked 11 years ago
Molarity and Mass percent.
Molarity and Mass percent.
1. A 2.5% solution concentration signifies that there are ___2.5g____of solute in every 100g of solution.

2. Therefore, when the mass percent concentration is expressed as a ratio of solute mass over solution mass, it would be__.025____

3. A solution mass of 1 kg is __10______times created than 100g, thus the mass of KI in a kilogram of a 2
Chemistry   Taylor14   9696   Asked 9 years ago
What is the correct value for Avogadro's number?
What is the correct value for Avogadro's number?
Question 1 of 12    4.0/ 4.0 Points
What is the correct value for Avogadro's number?

A. 6.022 × 102.3   

B. 6.022 × 1033   

C. 6.023 × 1022   
   

D. 6.022 × 1023   

E. none of the above   


Answer Key: D
Question 2 of 12    4.0/ 4.0 Points
What is the mass of 1.56 × 1021 atoms of magnesium in grams?
Chemistry   tater218   14582   Asked 12 years ago
A balloon filled with 0.500 L of air at sea level is submerged in the water to a depth that produces
A balloon filled with 0.500 L of air at sea level is submerged in the water to a depth that produces
Question 1 of 12    0.0/ 4.0 Points
A balloon filled with 0.500 L of air at sea level is submerged in the water to a depth that produces a pressure of 3.25 atm. What is the volume of the balloon at this depth?

A. 1.63 L   

B. 0.615 L   

C. 0.154 L   
   

D. 6.50 L   

E. none of the above   


Answer Key: C
Questi
Chemistry   tater218   10394   Asked 12 years ago
A 5.00-mL sample of a phosphoric acid solution of unknown concentration is titrated with a 0.1221 M
A 5.00-mL sample of a phosphoric acid solution of unknown concentration is titrated with a 0.1221 M
Part 1 of 1 -   27.0/ 50.0 Points
Question 1 of 12    4.0/ 4.0 Points
A 0.15 M solution of BaCl2 contains:

A. 0.30 M Ba2+ ions and 0.30 M Cl- ions.   

B. 0.30 M Ba2+ ions and 0.15 M Cl- ions.   
   

C. 0.15 M Ba2+ ions and 0.30 M Cl- ions.   

D. 0.15 M Ba2+ ions and 0.15 M Cl- ions.   

E. none of the above   


Ans
Chemistry   tater218   8994   Asked 12 years ago
Name the following compound: CH3-CH2-CH2-CH2-O-CH2-CH3
Name the following compound: CH3-CH2-CH2-CH2-O-CH2-CH3
Part 1 of 1 -   25.0/ 50.0 Points
Question 1 of 12    4.0/ 4.0 Points
Name the following compound: CH3-CH2-CH2-CH2-O-CH2-CH3

A. hexyl ether   

B. 2-hexone   
   

C. butyl ethyl ether   

D. ethyl butylone   


Answer Key: C
Question 2 of 12    0.0/ 4.0 Points
Which of the following statements is FALSE about polymers?
Chemistry   tater218   10231   Asked 12 years ago
Bond Length Differences
Bond Length Differences
What causes the difference in bond lengths in butane and tertbutyl cyclohexane?

Does it have something to do with stability?
Chemistry   tackett6   2738   Asked 11 years ago
Does anyone has any information on this forum, I have not had any luck!!!
Does anyone has any information on this forum, I have not had any luck!!!
In this discussion, you will be investigating the effects of acid rain in your location.

1. Identify your chosen area and include an image that shows an example of the effects of acid rain in your chosen area. If possible, find the example yourself and take your own picture. Explain the picture, what and where it is, what the damage is, if anything is being done about the
Chemistry   Steptim   580   Asked 10 years ago
Propane, C3H8, is flammable and used in rural areas where natural gas is not ava
Propane, C3H8, is flammable and used in rural areas where natural gas is not ava
Propane, C3H8, is flammable and used in rural areas where natural gas is not available. What is the coefficient of oxygen in the balanced equation for the combustion of propane?

   10
   7
   1
   5
   None of these
Chemistry   steelG   378   Asked 9 years ago
post erased
post erased
Post erased
Chemistry   Spice   431   Asked 10 years ago
Exam tomorrow!! Please help me solve this! I tried everything!!! (Acid/base pH calculation)?
Exam tomorrow!! Please help me solve this! I tried everything!!! (Acid/base pH calculation)?
Some hydrogen and iodone are mixed at 229 degrees C in a 1.00L container. When equilibrium is established, the following concentrations ar present:
[HI] = 0.490M
[H2] = 0.080M
[I2] = 0.060M

If an additional 0.300 moles of HI is then added, what concentrations will be present when the new equilibrium is established?

H2 + I2  2HI


please show me how to solve this. the answer
Chemistry   soccer1912   776   Asked 11 years ago
Calculating pH with pKa at certain ionization point?
Calculating pH with pKa at certain ionization point?
1) Lactic Acid has one acidic hydrogen with pKa=3.85. At what pH is lactic acid 3/4 ionized?

2) Ammonia has a pKa of 9.24. At what pH is ammonia 70% ionized?
Chemistry   smmrwds   606   Asked 11 years ago
A sample of technetium-99m has an activity of 1.5 Ci.?
A sample of technetium-99m has an activity of 1.5 Ci.?
A sample of technetium-99m has an activity of 1.5 Ci. How many disintegrations occur in the technetium-99m sample in 5.0 sec?
Chemistry   smmoh4   2682   Asked 11 years ago
What is the composition of the vapor of a pentane-hexane solution that has a vapor pressure of 361 Torr at 25C?
What is the composition of the vapor of a pentane-hexane solution that has a vapor pressure of 361 Torr at 25C?
I got 0.584 = mole fraction of pentane in vapor and 0.416 mole fraction of hexane in vapor.

Somehow it's wrong please help =(
Chemistry   SMK.ANOOP   1496   Asked 11 years ago
Determine the enthalpy change
Determine the enthalpy change
A typical automobile engine uses a lead-acid battery. During discharge, the following chemical reaction takes place: Pb (s) + PbO2 (s) + 2H2SO4 Rightwards Arrow 2PbSO4 (aq) + 2H2O (I)
Determine the enthalpy change of this reaction, given the following equations:

1) Pb (s) + PbO2 (s) + 2SO3 (g) Rightwards Arrow 2PbSO4 (s)   ΔH°= -775 kJ

2) SO3 (g) + H2O (I) Rightwards Arrow H2SO4
Chemistry   Smile23   154   Asked 3 years ago
Thinkwell Chem Lab #4 Help!
Thinkwell Chem Lab #4 Help!
I need help with the Thinkwell Chem Lab #4. Thanks!
Chemistry   sholland90   1496   Asked 12 years ago
What is the role of vacuum filtration in this process of Recrystallization?
What is the role of vacuum filtration in this process of Recrystallization?
(d) (2 pts.) What is the role of vacuum filtration in this process of Recrystallization? How do you do it?

Answer:
Chemistry   sholland90   2256   Asked 12 years ago
If a solution contains 28 g of potassium nitrate per 100 g of water at 25 degree
If a solution contains 28 g of potassium nitrate per 100 g of water at 25 degree
(e) (2 pts.) Suppose we are dealing with potassium nitrate as opposed to the chemical in the video. If a solution contains 28 g of potassium nitrate per 100 g of water at 25 degrees Celsius, is the solution unsaturated, saturated, or supersaturated? You may want to refer to Figure 13.4 in your text for help.

Answer:
Chemistry   sholland90   3961   Asked 12 years ago
Dilutions
Dilutions
You were working in a biomedical research lab. You needed to find 25 mL of 1.5x10-3 M aqueous solution of blue dye for your next experiment. After a thorough search, you found a bottle of 0.01M, stock solution of the blue dye. How do you dilute the stock solution to the concentration you needed? You need to write a procedure that contains step-by-step instructions to be followed in
Chemistry   sholland90   1187   Asked 11 years ago
Chem Lab Help
Chem Lab Help
From a manufactory’s production line, there are two types of soda products: Apple and Cherry flavors. Your job is to randomly select samples from the each product line and monitor the quality of the products from data you have measured. You have used the same protocol of analysis for both products. In an initial analysis, 535 samples of Apple soda and 653 samples of Cherry soda samp
Chemistry   sholland90   1147   Asked 11 years ago
Confident Interval
Confident Interval
From a manufactory’s production line, there are two types of soda products: Apple and Cherry flavors. Your job is to randomly select samples from the each product line and monitor the quality of the products from data you have measured. You have used the same protocol of analysis for both products. In an initial analysis, 535 samples of Apple soda and 653 samples of Cherry soda samp
Chemistry   sholland90   747   Asked 11 years ago
confident interval of the mean for the Cherry soda
confident interval of the mean for the Cherry soda
From a manufactory’s production line, there are two types of soda products: Apple and Cherry flavors. Your job is to randomly select samples from the each product line and monitor the quality of the products from data you have measured. You have used the same protocol of analysis for both products. In an initial analysis, 535 samples of Apple soda and 653 samples of Cherry soda samp
Chemistry   sholland90   934   Asked 11 years ago
confident interval of the initial production?
confident interval of the initial production?
From a manufactory’s production line, there are two types of soda products: Apple and Cherry flavors. Your job is to randomly select samples from the each product line and monitor the quality of the products from data you have measured. You have used the same protocol of analysis for both products. In an initial analysis, 535 samples of Apple soda and 653 samples of Cherry soda samp
Chemistry   sholland90   779   Asked 11 years ago
the mean of the initial test indeterminate or determinate error?
the mean of the initial test indeterminate or determinate error?
From a manufactory’s production line, there are two types of soda products: Apple and Cherry flavors. Your job is to randomly select samples from the each product line and monitor the quality of the products from data you have measured. You have used the same protocol of analysis for both products. In an initial analysis, 535 samples of Apple soda and 653 samples of Cherry soda samp
Chemistry   sholland90   869   Asked 11 years ago
Burning up or burning down?
Burning up or burning down?
An experiment was carried out to determine the chemical formula of a metal oxide (MxOy) by burning the metal. The similar experiment but using Magnesium is described in the previous article: "Stoichiometric experiment explained". You can also watch the video for the experiment from the last linked item.

The data from the experiment can be found from this module
Chemistry   sholland90   1132   Asked 11 years ago
1d. determine the number of grams of water required at 100 Celsius to dissolve a
1d. determine the number of grams of water required at 100 Celsius to dissolve a
1d. determine the number of grams of water required at 100 Celsius to dissolve a mixture containing 20 g KNO3 and 2.0 g CuSO4*5H20 assuming that the solubility of one substance is not affected by the presence of another.

2. to the solution in Problem 1d at 100 Celsius, 15g of water are added and the solution is cooled to 0 Celsius

Chemistry   sesait   3856   Asked 12 years ago
What is the theoretical yield (and limiting reagent) for this reaction?
What is the theoretical yield (and limiting reagent) for this reaction?
Preparation of K3[Fe(ox)3].3H2O

- Reagents include:
2.5 g of Fe2(SO4)3 (Ferric (III) Sulfate)
5.0 g of BaC2O4 (Barium Oxalate)
2.7 g of K2C2O4.H2O (Potassium Oxalate Monohydrate)

The balanced equation is as follows:

Fe2(SO4)3 + 3 BaC2O4 + 3 K2C2O4 → 2 K3[Fe(C2O4)3] + 3 BaSO4

Given the following molar masses (M):
Fe2(SO4
Chemistry   Sektor404   5775   Asked 9 years ago
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