Sunday

November 29, 2015
Total # Posts: 363

**Chemistry **

HELP!!! At temperatures above 930 ∘C, PbO reduces PbS to form metallic lead (Pb). The byproduct of the reaction is SO2. Calculate the amount of lead produced (in kg) when a reactor is charged with 487.0 kg of PbS and 750 kg of PbO.
*January 11, 2013*

**Chemistry**

A photon interacts with a ground state electron in a hydrogen atom and is absorbed. The electron is ejected from the atom and exhibits a de Broglie wavelength of 0.468×10−10 m. Determine the frequency (in hz) of the interacting photon.
*January 11, 2013*

**Chemistry**

HELP!!! Chacho At temperatures above 930 ∘C, PbO reduces PbS to form metallic lead (Pb). The byproduct of the reaction is SO2. Calculate the amount of lead produced (in kg) when a reactor is charged with 487.0 kg of PbS and 750 kg of PbO.
*January 11, 2013*

**Chemistry**

0.435
*January 11, 2013*

**Chemistry**

for a) no A NO B
*January 11, 2013*

**Chemistry**

3.27*10^-7
*January 11, 2013*

**math**

a rope was tied to trees at both ends the curve of the rope can be modelled by the equation y=x^2-12x where y is the height and x is the horizontal distance both in feet how far apart are the trees how do you know. show your work
*December 19, 2012*

**Physics**

A ship sailing through the St. Lawrence River (fresh water) enters the Atlantic Ocean (salt water). At equilibrium the ship will sit {higher or lower} in the Atlantic Ocean (salt water) compared to the St. Lawrence River (fresh water).
*December 18, 2012*

**,Math2**

calculate the cost per barrel if 4000 barrels were extracted from the ground C=9x2-144x+480000 this is a quadratic relation the 2 is a exoponet
*December 18, 2012*

**MATH**

if the minimum cost is $608.50 how many barrels are extracted in order to meet the minimum cost. C=9x2-144x+608.50 this is a quadratic relation that 2 is a exponet. please show your work
*December 18, 2012*

**Chemistry help please**

You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 359.5 ppm and is initially uniform through the thickness of the steel. The atmosphere of...
*December 16, 2012*

**Chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.3 kg m-3. Under these conditions the total surface area of the balloon is 0.33 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...
*December 16, 2012*

**Chemistry (balloon)**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.3 kg m-3. Under these conditions the total surface area of the balloon is 0.33 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...
*December 15, 2012*

**Chemistry**

Got the answer thanks anyway
*December 15, 2012*

**Chemistry**

Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−4 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free carriers/cm3) in...
*December 15, 2012*

**Chemistry**

I still didn't get it right
*December 15, 2012*

**Chemistry**

You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 359.5 ppm and is initially uniform through the thickness of the steel. The atmosphere of...
*December 15, 2012*

**Chemistry**

Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−4 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free carriers/cm3) in...
*December 14, 2012*

**math**

Graph each compound inequality. f>3 or f< -2 Which one do I graph? Im confused.....
*December 10, 2012*

**math**

Graph each compound inequality. f>3 or f< -2 Which one do I graph? Im confused.....
*December 10, 2012*

**Chemistry **

The fictitious compound, arrhenium fluoride ( ), reacts with itself to form a dimer with the formula Ah2F2 . The reaction is second order in AhF. The value of the rate constant is 8.591x10-3 M-1s-1. What is the initial rate of reaction in a reactor filled with AhF to a ...
*December 6, 2012*

**Chemistry**

Oops, I mean the molarity would decrease because moles base / larger quantity in L = a small # therefore decreased molarity. Correct?
*December 5, 2012*

**Chemistry**

Or if you didn't correct this error, the molarity of the base would be higher than it should be. Is that correct?
*December 5, 2012*

**Chemistry**

How will overshooting the end point of an acid-base titration by adding too much base to KHP affect the calculated molarity of the base? I would think you would need to add more KHP, then more base to bring it to the endpoint. So the molarity calculated should be the same. Is ...
*December 5, 2012*

**Chemistry**

You dissolve 20.0 gms of sucrose (sugar) in 200 mL of ethanol 20ºC (density of ethanol at 20ºC is 0.789 gm/ml). What is the mass % of the solute?
*December 3, 2012*

**Chemistry**

Concentrated aqueous ammonia contains 1.00 mol NH3 dissolved in 2.50 mol H2O. What is the mole fraction of NH3 in concentrated aqueous ammonia?
*December 3, 2012*

**Chemistry**

You dissolve 17.1 gms of sucrose (sugar) in 100 mL of ethanol 20ºC. What is the molarity (M)?
*December 3, 2012*

**Chemistry**

I figured it out if it contains the conjugate base of a strong acid
*December 2, 2012*

**Chemistry**

When will a salt produce a neutral solution? 1-if it contains the conjugate base of a strong acid 2-if it contains the conjugate base of a weak acid 3-if it contains the conjugate acid of a weak base
*December 2, 2012*

**Chemistry**

Is the equation of the chemical reaction that occurs when you blow your breath through boiling water? CO2 + H2O -> H + HCO3
*December 2, 2012*

**Chemistry**

How many mg of Ca^2+ are in one mEq? What I did was mg = mEq x mol weight / valence mg = 1 x 40.078/ 2 = 20 mg Is this correct?
*December 2, 2012*

**CRT 205**

I am having trouble finding the premise in the article Cyberbullying is Not Worse than Physical Bullying
*December 1, 2012*

**Chemistry**

Antacid tab is dissolved in water and a few drops of phenolphthalein is added yielding bright pink solution. 0.2025 M HCl added until pink color disappears. The 0.2147 M NaOH added until it turns light pink for ~30 seconds. mass on antacid tablet = 1.056g initial V 0.2025 M ...
*December 1, 2012*

**Chemistry**

So, Mols NaOH = 0.2264 M NaOH x 0.04936 L NaOH = 0.011175 Mols KHP = grams KHP / molar mass KHP or grams KHP = Mols KHP x molar mass KHP so 0.011175 x 204.22 = 2.2822 grams of KHP Is that correct DBob222?
*December 1, 2012*

**Chemistry**

How many grams of KHP (204.22 g/mol) were present in container if 49.36 mL of 0.2264M NaOH were needed to reach the end point of a titration? I'm confused on the formula you would use for this.
*December 1, 2012*

**math**

e/7-3=-5 What does e equal? Please show work!
*November 26, 2012*

**Physics**

A person consumes 2500 kcal/day while expanding 3500 kcal/day. In a months' time, about how much weight would this person lose if the loss were essentially all from body fat? (Body fat has an energy content of about 4100 kcal per pound).
*November 19, 2012*

**biology**

define natural selection
*November 14, 2012*

**Math**

ashworth
*November 14, 2012*

**Vocab2**

no its not b
*November 14, 2012*

**social studies**

mrs.sue can you tell me the answer please I cant find it.
*November 13, 2012*

**social studies**

What physical feature is in Africa that is located in the north and seperates it from Europe?
*November 13, 2012*

**social studies**

mrs.sue can you tell me the answer please I cant find it.
*November 13, 2012*

**math**

w-15=-9 w is a variable, I have to find what it equals
*November 7, 2012*

**7th grade science Ms. Sue please check**

Num 5 is A
*November 2, 2012*

**SS8R - HELP!**

He controlled some steel mill business that was very popular
*October 25, 2012*

**math**

Thank you mrs sue
*October 25, 2012*

**math**

Are their any easy ways to do these types of problems because im still a little confused and i have 14 problems still left to do
*October 25, 2012*

**math**

ms sue whats the entire answer?
*October 25, 2012*

**math**

what is the whole answer?
*October 25, 2012*

**math**

11x+12 or 11x-12 or am i totally wrong?
*October 25, 2012*

**math**

is it 11x+12 or 11x-12 or am i totally wrong?
*October 25, 2012*

**math**

is (10x+2)+(x-10) equal 9x-10 ms sue?
*October 25, 2012*

**math**

really! i didnt know it was that simple.if i do another ine will you check my answer please?
*October 25, 2012*

**math**

i got 2+10=12 ms sue
*October 25, 2012*

**math**

2+10=12
*October 25, 2012*

**math**

mrs sue is one the answer?
*October 25, 2012*

**math**

is x minus 10x = 9 because i replaced x with one
*October 25, 2012*

**math**

Im not sure what step to do first....
*October 25, 2012*

**math**

(10x+2)-(x-10) simplified please! Thank you,please show the work!
*October 25, 2012*

**math**

what is (-x-3)+(4x-7)simplified? please show the work, thenk you.
*October 25, 2012*

**math**

thank you emma and ms sue it really helped!
*October 25, 2012*

**math**

what is (14x-5)+(6x-4)simplified? Please help I would appreciate and PLEASE show the work!! Thank you!!
*October 25, 2012*

**English**

Proppeled is the verb i think it is active i hope this helped! By the way, I think it is active because you can be propelled
*October 25, 2012*

**Science**

You can say what ever type of plant or whatever your testing will work the best in the organic lab.Sorry if this dosen't help if you give me more details I can help you more.
*October 24, 2012*

**Social studies**

No boys have many sleepovers too.i have a freind who has boy\girl sleepovers.
*October 24, 2012*

**math**

plz help solve 6(4x+7)+x simply it plzz!thx for ur help
*October 24, 2012*

**physics**

Salmon often jump waterfalls to reach their breeding grounds. Starting 3.16 m from a waterfall 0.257 m in height, at what minimum speed must a salmon jumping at an angle of 37.9◦ leave the water to continue upstream? The acceleration due to gravity is 9.81 m/s2 . Answer ...
*October 16, 2012*

**Chemistry**

100 g of a clear liquid is evaporated and a few grams of white crystals remain. the original liquid was a..? Please help.
*October 8, 2012*

**accounting**

The journal entry to record the withdrawal of cash by Sue Snow, the owner, to pay a personal utility bill would include a debit to __________ and a credit to __________.
*September 21, 2012*

**Legal Transcription**

Exam No. 465802 Exam Name LEGAL TRANSCRIPTION PROJECT Need to see someones done exam
*August 21, 2012*

**human resources**

Why did the LRC determine that RAs and CDAs were employees? Do you agree with the LRC decision? Why? Why not?
*August 20, 2012*

**Math**

jim owns a square piece of land with a side length of a meters. he extends his property by purchasing adjacent land so that the length is increased by 10 m and the width by 12 m. write an algebraic expression for the area of jim's extended property
*May 23, 2012*

**social studies**

Why is the Rosetta Stone important..?
*April 29, 2012*

**Finance**

Hetfield and Ulrich, Inc., has an odd dividend policy. The company has just paid a dividend of $7 per share and has announced that it will increase the dividend by $5 per share for each of the next 4 years, and then never pay another dividend. If you require a 14 percent ...
*April 29, 2012*

**Algebra 2**

Suppose you roll two dice. Find the number of elements in the event space of rolling a sum of 2.
*April 26, 2012*

**Business Math**

The balance sheet of karim imports lists the following account balances: cash 6,450 supplies 1,200 accounts receiveable 15,360 office equipment 8,500merca
*April 20, 2012*

**business communication**

Which of the following would be the best revision of these sentences? "Our present receivables are in line with last year's. However, they exceed the budget. The reason they exceed the budget is that our goal for receivable investment was very conservative." A. &...
*April 14, 2012*

**Chem 112**

Which of the following contains the metal with the highest oxidation number? a. CaCl2 b. NaCl c. FeCl3 d. CuCl2
*April 12, 2012*

**math**

67.2 = mean 10.03= SD percentage=48.81%
*April 12, 2012*

**Math**

The ratio of Maya's beads to Kayla's beads was12:7. After Maya bought another 28 beads and Kayla gave away 32 beads, 5/7 of Kayla's beads were left. How many more beads did Maya have than Kayla in the beginning? Find the ratio of Maya's beads to Kayla's ...
*April 8, 2012*

**Math**

If Will gives Molly $9 he will have the same amount as her. If Molly gives will $9 the ratio of the money she has to the money Will has will be 1:2. How much money does Will have in the beginning
*April 7, 2012*

**Statistics**

How do you calculate the percentage of women that have weights between 140 lb and 220 lb with a mean of 145 lb and a standard deviation of 31 lb?
*April 7, 2012*

**geometry**

the pentagons are similar. the area of the smaller pentagon is 30m squared. what is the area of the larger pentagon in m squared?
*March 29, 2012*

**physics**

a) (304/26.7)*2 = 22.8 b) 26.7/22.8 = 1.173
*March 28, 2012*

**pre-algebra**

you have twice as many dimes as you do nickels and two more quarters than nickels that equals $2.50
*March 21, 2012*

**critical thinking**

1. Identify areas of environmental concerns. According to the area that the Bivouac site will be set, it will be an area where there will be hills, wetlands (water source), several winding streams, and one large river and some marked-off archeological sites. This are the ...
*March 8, 2012*

**Physics**

An audible standing wave is produced when air is blown across a pipe that is open at both ends. If the pipe is 29 cm tall, what is the frequency of sound produced?
*March 5, 2012*

**math**

there were 490 altogether in 2 groups. group A consited of only boys and group b constied of only girls. ther were 2 and a half times as many girls as boys. some girls joined group b and foe every 4 boys in group a 32 more boys jioned the group. the total number og girls was ...
*March 1, 2012*

**Math**

Tap A was turned on to fill a rectangular tank of 50 cm by 40 cm by 28 cm with water at a rate of 6 liters per minute. After 2 minutes, Tap B was turned on to drain water from the tank at a rate of 2 liters per minute. 6 minutes after Tap B was turned on, both taps were turned...
*February 28, 2012*

**PSY**

The correct answer is D
*February 20, 2012*

**Psychology**

Sally is driving her car and talking on her cell phone. Statistically this behavior has been shown to be quite dangerous and contributes to many automobile accidents. In performing these two tasks simultaneously, Sally uses: a. conscious cognitive processes b. mindless ...
*February 20, 2012*

**Psychology**

The majority of psychologists are electric, which means they draw information from different schools of thought rather than limiting themselves to information gained from only one perspective. However, most psychologists agree that it's important to: a. gather empirical ...
*February 20, 2012*

**HELP 15**

defiantly not i got that wrong on my exam
*February 19, 2012*

**HELP12**

its not b i got that wrong
*February 19, 2012*

**HELP11**

i marked that and got that wrong
*February 19, 2012*

**Additional maths**

Given one of the roots of the quadratic equation x^2+kx=12 is one third the other root. Find the possible values of k.
*February 1, 2012*

**math**

If Julie bought 8 T-shirts, she would be short $28. If she bought 4 T-shirts and 3 baseball hats, she would have $17 left. If each hat cost $5, how much money did she have in the beginning?
*January 22, 2012*

**math**

every week Brady gets $2.50 more for his allowance than Max does. They spend $6 on snacks and save the rest. Brady saves $72, but Max saves only $52. How many weeks does it take Brady to save $72? Hoe much money does Max get every week?
*January 22, 2012*