Saturday

July 30, 2016
Total # Posts: 616

**Chemistry**

A solution is prepared by dissolving NH3(g) in water according to the following equation. NH3(g) + H2O(l)=NH4^+(aq)+ OH^-(aq) If the pH= 9.60 what is the [OH-] in the solution.
*November 30, 2011*

**Chemistry**

q= 20.00 C =125.0g x 98.0 C x 25.80 C -20.00??
*November 30, 2011*

**Chemistry**

still dont get it
*November 30, 2011*

**Chemistry**

a coffee cup calorimeter normally consists of two nested styrofoam cups with a lid. a coffee cup calorimeter of this type contains 125.0 g of water at 20.00 degrees C. A 120.0 g sample of copper metal is heated to 98.0 degrees C by putting it into a beaker of hot water. The ...
*November 30, 2011*

**geometry**

They made a perfect pear
*November 16, 2011*

**Chemistry**

IS THIS RIGHT? Experiments were performed with four metals and solutions of their ions: A-A^+, B-B^2+, C-C^2+, D-D^2+. The results of the experiments were: D^+2 + C ---> No reaction B^+2 + C---> B + C^+2 A^+ + B ---> A + B^+2 a.) Write the equation for each reduction ...
*November 7, 2011*

**math**

i am having trouble with two digit dividends. here is an example 34 divided 264
*November 1, 2011*

**Physics**

A rock is projected from the edge of the top of a building with an initial velocity of 19.6 m/s at an angle of 31 degrees above the horizontal. The rock strikes the ground a horizontal distance of 77 m from the base of the building. The acceleration of gravity is 9.8 m/s^2.(...
*November 1, 2011*

**physics**

A rock is projected from the edge of the top of a building with an initial velocity of 19.6 m/s at an angle of 31 degrees above the horizontal. The rock strikes the ground a horizontal distance of 77 m from the base of the building. The acceleration of gravity is 9.8 m/s^2.(...
*November 1, 2011*

**physics**

A spy in a speed boat is being chased down a river by government officials in a faster craft. Just as the officials' boat pulls up next to the spy's boat, both boats reach the edge of a 4.8 m waterfall. The spy's speed is 16 m/s and the officials; speed is 26 m/s. ...
*November 1, 2011*

**english**

rewrite these sentences into reported speech. 1-where did you get these dress? 2-who did these dress belong to? 3-where do you buy your clothes? 4-how long have you been collecting these clothes? 5-what will you wear at the party? 6-why are you decorating the house? 7-what ...
*October 25, 2011*

**math**

Vin paid $60 for 4 new DVDs. His friend Samuel paid $78 for 6 new DVDs. Who got a better deal?
*October 19, 2011*

**physics**

A particle starts from the origin at t = 0 with an initial velocity of 5.5 m/s along the positive x axis.If the acceleration is (-2.8i + 4.1jm/s^2, determine (a)the velocity and (b)position of the particle at the moment it reaches its maximum x coordinate.
*October 16, 2011*

**solid mechanics 1**

a load P is supported
*October 12, 2011*

**solid mechanics 1**

a load p is supported by a steel pin that has been inserted in a short wooden member hanging from the ceiling. the ultimate strength of the wood used is 60 MPa in tension and 7.5 MPa in shear, while the ultimate strength of the steel is 145 MPa in shear. knowing that b= 40 mm...
*October 7, 2011*

**spanish**

what is the difference gramtically between these two sentences Necesitamos sillas más cómodas. Se necesitan sillas más cómodas.
*October 5, 2011*

**chemistry**

How many moles of carbon, hydrogen, and oxygen are present in a 100g sample of ascorbic acid?
*October 4, 2011*

**science**

Is volume the amount of space an object takes up?
*September 25, 2011*

**MAth**

rewrite it as an addition problem. -4.8 + 4.9 = what? And then add 5.7 to your answer of -4.8 + 4.9 and that would be your answer.
*September 25, 2011*

**math**

Nonr
*September 22, 2011*

**physics**

With an average acceleration of -.56 m/s2, how long will it take a cyclist to bring a bicycle with an initial speed of 13.3 m/s to a complete stop?
*September 22, 2011*

**English**

It would be a metaphor-is that correct?
*September 20, 2011*

**English**

1.What figure of speech is this? I think it is personification "Death stands above me, whispering low I know not what into my ear." simile litotes personification metonymy synecdoche 2.What figure of speech is this:The fog comes on little cat feet This one I hav no ...
*September 20, 2011*

**Physics**

A female gymnast weighs 400 N. If she is hanging stationary from a high bar, how many forces are acting on her?
*September 11, 2011*

**Chemistry**

concentration of Cl2 will be 0.0084 mol/L concentration of NO will be 0.017mol/L This is because there are two moles of NO but only one mol of Cl2. We obtain the concentration of Cl2 by calculating the number of moles (from the ratio) and dividing this by the volume you ...
*September 8, 2011*

**science**

design an expirament to test if the price of the gasoline affects the mileage in my car. find the dependent variable.
*September 5, 2011*

**Science**

bouyant force i think.
*September 4, 2011*

**calculus**

can you explain how you got both answers?
*August 8, 2011*

**calculus**

i dont understand the last step. how did you get to -1 + e^3 -1 = -2 + e^3
*August 8, 2011*

**calculus**

Find the sum of the series 2 + 9/2! + 27/3! + 81/4! . . .
*August 8, 2011*

**Grammar**

Unable to find her driver's license, Mary asked the agent whether a credit card would be sufficient enough evidence to prove her identity. Here, "sufficient enought" is the error. But I do not know why that is. Please explain in details! Thank you.
*August 1, 2011*

**Chemistry :)**

Balance the following redox equation and identify the element oxidized, the element reduced, the oxidizing agent, and the reducing agent. Show all of the work used to solve the problem. NO2- + Al AlO2- + NH3 Thanks :)
*June 19, 2011*

**math**

x+y+3z=600 x+y+z=400 1. In the system of equations above, what is the value of x+y? 2. There are 25 trays on a table in the cafeteria. Each tray contains a cup only, a plate only, or both a cup and a plate. If 15 of the trays contain cups and 21 of the trays contain plates, ...
*June 17, 2011*

**grammer**

firt grade, a diamante, noun, then two adjectives, then verbs ending in ed or ing, then related nouns, then more ing/ed verbs, adjectives, then noun.
*June 13, 2011*

**grammer**

what is a related noun? mom and i are stuck.
*June 13, 2011*

**algebra**

100.1
*May 27, 2011*

**Chemistry**

I forgot to add that in my experiment I used 1.2 grams of 10-52-10 plant food ( + 4 grams MgSO4 7H2O) and obtained 2.30 g of MgNH4PO4 6H20
*May 27, 2011*

**Chemistry**

need to calculate percent yield of MgNH4PO4 . 6H2O obtained in my experiment using 10-52-10 plant food label as a guide to determine the theoretical yield of MgNH4PO4 . 6H2O. My calculations so far: air dry weight of MgNH4PO4 . 6H2O = 2.30 g Grams of phosphorusin MgNH4PO4 ...
*May 27, 2011*

**Science**

I have no idea :)
*May 4, 2011*

**Algebra**

something
*May 1, 2011*

**Physics**

All right. Think of the trap door as a bar and draw a free-body diagram (FBD) with it as such. Assuming this is a uniform system, the center of mass will also be at the center of the door and that is also where gravity will be pulling on the door. Since the door is cocked at ...
*April 27, 2011*

**Physics**

A trap door, of length and width 1.65 m, is held open at an angle of 65.0 degrees with respect to the floor. A rope is attached to the raised edge of the door and fastened to the wall behind the door in such a position that the rope pulls perpendicularly to the trap door. If ...
*April 27, 2011*

**stats**

salary study conducted. mean for men = $42,000. Std deviation = $9,000. mean for women = $39,000. Std dev for women = 8,000. If 100 men surveyed, at a CI of 95% what is the the most number of women surveyed if there was no Statistical difference in the mean for men and women?
*April 26, 2011*

**Algrebra**

What goes into 12 that goes into 36? 4 goes into 12 3 times and into 36 9 times. This can be simplified again by 3s. 3 goes into itself 1 time and into 9 3 times. So, your final answer would be 1/3rd.
*March 10, 2011*

**algebra 2**

I am not sure what "Solve each system" means, but I would assume with the given information that you need to solve for "c", then solve for "d" with the answer to "c". To do that, your equation would look like this.... 3c+2(4) = 2 3c+8 = ...
*March 10, 2011*

**Finance**

Ms. Sue, thank you for sending me this link. I am having trouble putting the pieces together to fit my problem above. Could you perhaps expain it a little further?
*March 10, 2011*

**Finance**

A U.S. Firm wants to raise $10 million of capital so it can invest in new technology. How much will it need to raise in order to net $10 million, using the average costs of raising funds.
*March 10, 2011*

** grade 4 math**

thank you!
*February 28, 2011*

** grade 4 math**

is that the answer?
*February 28, 2011*

** grade 4 math**

Several friends are taking turns flying akite. Each friend flies the kite for the same amount of time.They spend 6 hours flying the kite altogether. Explain whatinformation you need to find how long each friend flew thekite for.
*February 28, 2011*

**math**

Tierra, Nico, and Alex had $865 altogether. Tierra spent 2/5 of her money. Nico spent $40,and Alex spent twice as much as Tierra. If the three had the same amount of money left, how much money did alex have in the begging?
*February 24, 2011*

**math**

Tierra, Nico, and Alex had $865 altogether. Tierra spent 2/5 of her money. Nico spent $40,and Alex spent twice as much as Tierra. If the three had the same amount of money left, how much money did alex have in the begging?
*February 24, 2011*

**math**

Tierra, Nico, and Alex had $865 altogether. Tierra spent 2/5 of her money. Nico spent $40,and Alex spent twice as much as Tierra. If the three had the same amount of money left, how much money did alex have in the begging?
*February 24, 2011*

**Physics-Could someone please help me?**

Could someone provide me with a simple explanation of how the Doppler Effect is used to determine the speed and direction of moving object
*February 23, 2011*

**Chemistry**

How many kJ will be released as 575 g of steam at 176 degrees celsius are changed into ice at -75 degrees celsius?
*February 22, 2011*

**Chemistry**

How many kilojoules of heat energy are needed to change 49.6 g of ice at 15 degrees celsius to water at 58 degrees celsius? I am having trouble figuring out how to solve this.
*February 22, 2011*

**Physics-Please help**

Could someone provide me with a simple explanation of how the Doppler Effect is used to determine the speed and direction of moving object
*February 22, 2011*

**Math**

When I do 12 times 9.5 do I do 12 x 9.5 OR 12 x9.5 but I am pretty sure it is the first one. Thank you so much!
*February 21, 2011*

**Math**

4th word is HOW not hw
*February 21, 2011*

**Math**

To find out hw much inches are in 9.5 feet, do I do 12 times 9.5? I would do that because there is 12 in. in a foot.
*February 21, 2011*

**physics**

Roxanne is making a strawberry milkshake in her blender. A tiny .0050-kg strawberry is rapidly spun aroundhe inside of the container with a speed of 14.0 m/s, held by a force of 10.0N. What is the radius of the blender at this location?
*February 20, 2011*

**Physics**

Nevermind. I got something close to what I think I'm supposed to get (I calculated 3.71 s). The only thing is, when I plug my time back into the equation to check for correctness, I end up getting a negative 78.4 m, which obviously doesn't equal positive 78.4 m. Any ...
*February 13, 2011*

**Physics**

A brick is thrown vertically upward with an initial speed of 3.00 m/s from the roof of a building. If the building is 78.4 m tall, how much time passes before the brick lands on the ground? I think I may have gotten part of this question by first calculating how long it takes ...
*February 13, 2011*

**math**

what does squared and cubed mean?
*February 9, 2011*

**Question**

Does it have to be about math?
*February 9, 2011*

**Social Studies**

Is it in your book?
*February 9, 2011*

**math**

what is 6*10^9=
*February 7, 2011*

**math**

what is 3*10^6=
*February 7, 2011*

**math**

In bengal, india and Bangladashthere are about 2.6*10 to the power of 8. What is 2.6*10 to the power of 8 ?
*February 7, 2011*

**math**

u/5=1.9 what is u
*February 7, 2011*

**statistics**

Three percent of all items sold by a mail-order company are returned by customers for a refund. Find the probability that of two items sold during a given hour by this company both will be returned for a refund
*February 7, 2011*

**math**

i dont know
*February 7, 2011*

**Question**

Thankyou
*February 7, 2011*

**Question**

Are students allowed to answer questions if we know them?
*February 7, 2011*

**Spanish**

Hello I was wondering if a fluent spanish speaker could look over my essay for spanish?
*January 12, 2011*

**chem/plz/check work studying for a final**

23. A 32.3 L sample of a gas at 305oC and 1.20 atm is to be cooled at constant pressure until its volume becomes 28.4L. What will be the new gas temperature? Tf = Vf*Ti/Vi Tf =28.4L x (305+273)K / 32.3L = (28.4)(578)K / 32.3 = 16415.2/32.3 Tf = 508K I got this one wrong on a ...
*December 16, 2010*

**chem/plz/check work studying for a final**

I guess I need to figure out the s.f. or stop rounding numbers.... :( thank you...
*December 16, 2010*

**chem/plz/check work studying for a final**

what is the volume occupied by 16.0g ethane gas (C2H6) at 720 Torr and 18C? V=nRT/P conversion of mol: 16.0g C2H6 X 1mol C2H6/30.07g C2H6= .53mol C2H6 V= .53 mol(0.0821 L*atm/mol*K)(291)K / 720 Torr (1 atm/760Torr) V= 13.5 L
*December 16, 2010*

**chem/thank you DrBob22**

thank you so much....your good, I wish you be my teacher I be passing my class with no problem....
*December 16, 2010*

**chem/plz/check work studying for a final**

A 20.5 lb cast iron boat anchor displaces 1.33 qt of water when submerged. What is the density of the cast iron, in g/cm3? 1L=1.057 qt 1kg=2.205lb 1lb=453.6g 20.5lb X 453.6g/ 1lb = 9298.9g 1.33qt X 1L/1.057qt = 1.26L 1.26L X 1000cm3/1L = 1260cm3 9298.9g/1260cm3 = 7.38g/cm3 **...
*December 16, 2010*

**chem/plz/check work studying for a final**

what is the volume occupied by 16.0g ethane gas (C2H6) at 720 Torr and 18C? V=nRT/P conversion of mol: 16.0g C2H6 X 1mol C2H6/30.07g C2H6= .53mol C2H6 V= .53 mol(0.0821 L*atm/mol*K)(291)K / 720 Torr (1 atm/760Torr) V= 13.5 L
*December 16, 2010*

**algebra**

Factor x2 - 100
*December 15, 2010*

**chemistry**

how many grams of CaCl2 must be dissolved to make 2.15 L of 0.05020 M Cl
*December 14, 2010*

**chemistry**

how many grams of CaCl2 must be dissolved to make 2.15 L of 0.05020 M Cl
*December 14, 2010*

**italian language**

A )Completare le farsi con il pronome personale opportune e con le desinenze del participio passato. 1-ALESSIA HA VINTO IL PRIMO PREMIO? ____GLI________ TELEFONO SUBITO E ____GLI _____DICO , SARA FELICISSIMA. 2- DEI COMPAGNI DI CLASSE HO RIVIST_O__SOLTANTO DUE . 3-ALBERTO E ...
*December 8, 2010*

**italian**

A )Completare le farsi con il pronome personale opportune e con le desinenze del participio passato. 1-ALESSIA HA VINTO IL PRIMO PREMIO? ____GLI________ TELEFONO SUBITO E ____GLI _____DICO , SARA FELICISSIMA. 2- DEI COMPAGNI DI CLASSE HO RIVIST_O__SOLTANTO DUE . 3-ALBERTO E ...
*December 8, 2010*

**math**

6:4
*December 7, 2010*

**11th grade**

In the Bohr model of the hydrogen atom, the speed of the electron is approximately 2.17 x 10^6 m/s. find the central force acting on the electron as it revolves in a circular orbit of radius 5.42 x 10^-11m.
*December 5, 2010*

**Chemistry College**

One reaction of iron with hydrochloric acid is represented by the following thermochemical equation. Fe(s) + 2HCl(aq) → FeCl2(aq) + H2(g); ΔH°= –87.9 kJ How much heat is liberated at constant pressure if 0.416 g of iron reacts with 42.0 mL of 0.457 M HCl? A...
*December 2, 2010*

**chemistry**

The answer doesn't fit with the choices given.
*December 2, 2010*

**college**

I believe it's suppose to be Pi/4 radians
*November 30, 2010*

**chem/some1 check my work plz.**

thank you for all your help Drbob222...just whish me luck for tomorrow in my test... :)
*November 16, 2010*

**chem/some1 check my work plz.**

air bags actived when a severe impact causes a steel ball to compress a spring and electrically ignite a detonator cap. this causes NaN3 to decompose explosively according to the following reaction: 2NaN3(s)=2Na(s)+3N2(g) what mas of NaN3 must be reacted to inflate an air bag...
*November 16, 2010*

**chem/some1 check my work plz.**

nitrogen gas contained in a cylinder with a volume of 5.0x10^2 mL @ a temp of 30C and pressure of 710 torr. The gas is then compresse to a volume of 25mL and the temp. is reaised to 820C. what is the new pressure of the nitrogen gas?? Pf=p1*v1*t1/Tf*Vf P=(700torr)(5.02x10^2mL...
*November 16, 2010*

**chem/some1 check my work plz.**

air bags actived when a severe impact causes a steel ball to compress a spring and electrically ignite a detonator cap. this causes NaN3 to decompose explosively according to the following reaction: 2NaN3(s)=2Na(s)+3N2(g) what mas of NaN3 must be reacted to inflate an air bag ...
*November 16, 2010*

**chem/some1 check my work plz.**

Thank u!!!!
*November 16, 2010*

**chem/some1 check my work plz.**

2NH3(g)+3CuO(s)=N2(g)+3Cu(s)+3H2O(g) if 18.1grams of ammonia reacts with 90.4 grams of copper(II) oxide, which is the limitting reagent?? what is the theorectical yield of nitrogen gasd? if 8.52 g of N2 are formed, what is the % yield of nitrogn gas?? please check if is ...
*November 16, 2010*

**chem**

thank u so much...
*November 15, 2010*

**chem**

An ideal gas in contained in a cylinder with a volume of 5.0x102mL at a temperature of 30C and a pressure of 710 torr. The gas is then compressed to a volume of 25mL, and the temperature is raised to 820C. What is the new pressure of the gas?
*November 15, 2010*

**chem**

ok..I see what i did wrong...thank u..ur the best!!!
*November 15, 2010*