Monday

October 24, 2016
Total # Posts: 720

**Chemistry**

Calculate the pH of a solution that results from the mixture of 50.0 mL of 0.15 M HCOOH with 75.0 mL of 0.13 M HCOONa. Now, don't forget these solutions are being mixed and you haven't accounted for that yet in the concentrations! Ka for HCOOH is 1.8 x 10-4.

*February 27, 2011*

**Chemistry**

Calculate the concentration of all species in a 0.15 M KF solution. Ka = 6.4 x 10-4 for HF.

*February 27, 2011*

**Chemistry**

Which one of the following pairs of reactants would react together in a Lewis Acid/Lewis Base reaction? a. KOH and HNO2 b. NaOH and HCl c. CH3COOH and HF d. Ag+ and NH3 e. HClO and NH3

*February 27, 2011*

**Chemistry**

If each of the salts listed in A through E were dissolved in water to make a 0.1 M solution, which solution would have the lowest pH? a. NaNO2 b. NaF c. AlCl3 d. KNO3 e. Na3PO4

*February 27, 2011*

**Chemistry**

The pH of a 0.065 M solution of a weak base is 11.70. What is the value of Kb for this base?

*February 27, 2011*

**Math**

=x^2+4x+4+x^2+6x+8 =2x^2+10x+12 =2(x^2+5+6) =(x+2)(x+3) =x=-3,-2

*February 22, 2011*

**Math**

If independent events have probabilities p and q, what are the odds of at least one of the events occurring?

*February 22, 2011*

**Math**

An experiment has probability p of success, q of failure and 1 - p - q of neither, If independent trials are repeated over and over until either success or failure is obtained, what is the probability of an ultimate success?

*February 22, 2011*

**chem**

Complete the table below: Answer the following for a body centered unit cell. (Hint: Helpful information can be found by going to the "Lattice" menu, choosing "Cubic", and then choosing "Body-Centered" in the Crystalline Solids program.) ...

*February 21, 2011*

**Calculus please help**

please help I can not understand this. I need an implicit form answer for the general solution of differential equation dy/dx=2(e^x-e^-x)/y^2(e^x+e^-x)^4 with (y>0). I have seperated the y^2 to the left hand side to become 1/3y^3 but have no idea how to make the right hand...

*February 18, 2011*

**physics**

Tarzan tries to cross a river by swinging from one bank to the other on a vine that is 9.0 m long. His speed at the bottom of the swing is 8.8 m/s. Tarzan does not know that the vine has a breaking strength of 1.0 103 N. What is the largest mass that Tarzan can have and still ...

*February 18, 2011*

**physics**

Tarzan tries to cross a river by swinging from one bank to the other on a vine that is 9.0 m long. His speed at the bottom of the swing is 8.8 m/s. Tarzan does not know that the vine has a breaking strength of 1.0 103 N. What is the largest mass that Tarzan can have and still ...

*February 18, 2011*

**Chemistry**

If the column of water in the water barometer fore to a height of 35ft, what would the atmospheric pressure be in mm Hg? mmH20X(density of water/density of Hg)= mmHg Density of water=0.99707 Density Hg=13.5340

*February 11, 2011*

**math**

im in the 5th grade and i need help is on metric measures and conversoins

*February 9, 2011*

**Business and Administrative Communications**

Identify the complete sentence that is correctly punctuated. a. Most people support the sex offender registry, I worry that this information will promote discrimation. b. Most people support the sex offender registry; and I worry that this information will promote discrimation...

*February 5, 2011*

**Algebra**

Use the remainder theorem to findvP(-2) for P(x)=2x^4+4x^3-5x^2+4. Specifically, give the quotient and the remainder for the associated division and the value of P(-2). Quotient= Remainder= P(-2)=

*February 5, 2011*

**Chemistry**

what mass of water at 15C can be cooled 1C by heat necessary to melt 185g of ice at 0C

*February 4, 2011*

**health...help plzz**

Explain the difference between a Doctor of Dental Surgery and Doctor of Medical Dentistry. Explain the difference between an allopathic and osteopathic physician.

*January 30, 2011*

**physics**

The answer is cheese. We always need cheese

*January 28, 2011*

**physics**

A student presses a book between his hands, as the drawing indicates. The forces that he exerts on the front and back covers of the book are perpendicular to the book and are horizontal. The book weighs 30.0 N. The coefficient of static friction between his hands and the book ...

*January 27, 2011*

**physics**

A 49-kg bungee jumper has fallen far enough that her bungee cord is beginning to stretch and resist her downward motion. Find the force (magnitude and direction) exerted on her by the bungee cord at an instant when her downward acceleration has a magnitude of 7.3 m/s2. Ignore ...

*January 27, 2011*

**physics**

A 1790-kg car is traveling with a speed of 15.6 m/s. What is the magnitude of the horizontal net force that is required to bring the car to a halt in a distance of 78.4 m?

*January 27, 2011*

**AP Calculus**

I'm confused as to how to do part C), I don't remember how to find the second derivative of an implicit differentiation problem!

*January 26, 2011*

**Help Please!**

Charges of −4q are fixed to diagonally opposite corners of a square. A charge of + 5q is fixed to one of the remaining corners, and a charge of + 3q is fixed to the last corner. Assuming that ten electric field lines emerge from the + 5q charge, sketch the field lines ...

*January 24, 2011*

**physics**

A large box whose mass is 20 kg rests on a frinctionless floor. A mover pushes on the box with a force of 250 N at an angle of 35 degrees below the horizontal. What is the acceleration of the box across the floor?

*January 16, 2011*

**economics**

It's D

*December 22, 2010*

**Economics**

Thank you so much. :)

*December 11, 2010*

**Economics**

Topic- Each students will pick three things to write a consumer report on. It's your choice. Compare-For each item that you pick you will need to pick two other items to compare it against. (if you choice restaurants, then you need to pick one, then pick two other ...

*December 11, 2010*

**Trig**

a student says there can only be 360 different rays emanating from a point since there are only 360 degrees in a circle. Is this true? Why or Why not?

*December 10, 2010*

**Physics**

A 0.075 kg ball in a kinetic sculpture moves at a constant speed along a motorized conveyor belt. The ball rises 1.32 m above the ground. A constant frictional force of 0.350 N acts in the direction opposite the conveyor belt's motion. What is the net work done on the ball?

*December 9, 2010*

**Chemistry**

Cesium-137 has a half life of 30.0 years. If initially there are 8.0 kg of cesium-137 present in a sample, how many kg will remain after 60.0 years?

*December 7, 2010*

**Math**

a percentage bar graph is sometimes used like a circle graph. If the bar is 8 cm, how long is each piece?

*December 1, 2010*

**Math**

How can the faces of two cubes be numbered so that when they are rolled, the resulting sum is a number 1 to 12 inclusive and each sum has the same probability?

*November 22, 2010*

**Physics**

Me also

*November 21, 2010*

**Physics**

For a certain transverse wave, the distance between two successive crests is 3.11 m, and 5 crests pass a given point along the direction of travel every 12.16 s. Calculate the wave speed.

*November 21, 2010*

**Chemistry**

Two samples of water of equal volume are put into two dishes and kept at room temperature for several days. The water in the first dish is completely vaporized after 2.8 days while the water in the second dish takes 8.3 days to completely evaporate.What can you conclude about ...

*November 18, 2010*

**Math**

A man collected $28500 on a loan of $25000 he made 4 years ago. If he charged simple interest, what was the yearly interest rate?

*November 13, 2010*

**Physics**

a skateboarder moving at v = 4.8 m/s along a horizontal section of a track that is slanted upward by 48° above the horizontal at its end, which is h = 0.54 m above the ground. When she leaves the track, she follows the characteristic path of projectile motion. Ignoring ...

*November 11, 2010*

**math**

Please help me do these problems. I don't understand how to do weighted averages. Mrs. Gleason invested a portion of 32000 dollars at 9% interest and the balance at 11% interest. How much did she invest at each rate if her total income from both investments was 3200

*November 9, 2010*

**Physics**

A 0.145 kg baseball pitched at 38.0 m/s is hit on a horizontal line drive straight back toward the pitcher at 55.0 m/s. If the contact time between bat and ball is 3.40×10−3 s, calculate the average force between the ball and bat during contact.

*November 8, 2010*

**physics**

Use the work-energy principle: Wnet=1/2mv^2-1/2mv^2 Initial velocity is zero therefore: Wnet=1/2mv^2 Ans: 4.3 m/s

*November 7, 2010*

**physics**

A 2.99 kg ball is dropped from the roof of a building 161.9 m high. While the ball is falling to Earth, a horizontal wind exerts a constant force of 12.3 N on the ball. How long does it take to hit the ground> The acceleration of gravity is 9.81 m/s2. Answer the units in s...

*November 7, 2010*

**college english**

what are some things I can include in an essay about Hoagland's "City Rat" Please don't reply with links. I can do that myself.

*November 7, 2010*

**fraction**

10 3/5 x 20/25

*October 28, 2010*

**5th grade word problem**

got 5 bithes

*October 26, 2010*

**physics**

is the force exerted by the wall on the person’s hand passive or active?

*October 22, 2010*

**physics**

is the force exerted by the wall on the person’s hand passive or active?

*October 22, 2010*

**physics**

2. Explain how the tension force gets transmitted along from one end of a string to the other. Does the amount of force that gets transmitted depend on how elastic or stretchable the string is? Explain.

*October 22, 2010*

**algebra**

train A and B are traveling in the same direction on parallel tracks. train A is going 80 miles per hour train B is going 84 miles per hour. train A past a station at 2:15 am train B passes at 2:45 am what time will train B catch train A

*October 21, 2010*

**Ap Chemistry**

Find the emf for the cell Cr(s) |Cr3+(aq, 0.37 M) || Pb2+(aq, 0.0095 M) | Pb(s). Answer in units of V I kept getting .55V but it is wrong. Can someone please help me?

*October 21, 2010*

**6th grade math**

Idk I have the same answer on my math ws

*October 21, 2010*

**AP CHEM**

Complete and balance the reaction Al(s) + Pb2+(aq) ! using the smallest possible integers. I got: 2Al(s) + 3Pb2 ==> Al2Pb3 Calculate the standard free energy. Faraday’s constant is 96485 J V · mol Answer in units of kJ/mol. I know the formula is -nFE but when I ...

*October 21, 2010*

**ap chemistry**

Find the emf for the cell Cr(s) |Cr3+(aq, 0.37 M) || Pb2+(aq, 0.0095 M) | Pb(s). Answer in units of V I got .548733V Is this right?

*October 21, 2010*

**ap chemistry**

I got 8*10^-8 Is this correct?

*October 19, 2010*

**ap chemistry**

A solution is prepared in which a trace or small amount of Fe+2 is added to a much larger amount of solution in which the [OH]- is 1.0M*10^-2. some Fe(OH)2 precipitates. the value of Ksp for the salt is 8.0*10^-10. assuming that the hydroxide ion concentration is 1.0M*10^-2 ...

*October 19, 2010*

**ap chemistry**

would the half reactions for Ag(s) |AgCl(s) |Cl−(aq) || Cl−(aq) |Hg2Cl2(s) |Hg(§¤)be Ag+Cl+e==> AgCl 2Cl+3Hg==>Hg2Cl2+Hg+e

*October 15, 2010*

**ap chemistry**

i am having trouble writing the half reactions and the balanced equation for the galvanic cell Ag(s) |AgI(s) | I−(aq) || Cl−(aq) |AgCl(s) |Ag(s)

*October 15, 2010*

**ap chemistry**

Thank you Dr. Bob. with that information I figured out my question.

*October 15, 2010*

**ap chemistry**

is it a double replacement reaction? 2NaNO3 + Hg2Cr2O7

*October 15, 2010*

**ap chemistry**

what is the galvanic cell for the redox reaction between sodium dichromate and mercury(I) nitrate in an acidic solution.

*October 15, 2010*

**calculus**

Find dy/dx by implicit differentiation. sin x = x (1 + tan y)

*October 14, 2010*

**ap chemistry**

A titration. 12.46 mL of KMnO4 are titrated with 25 mL of H2C2O4. The half reaction is 2H2O+H2C2O4 ARROW 2H2CO3+2H+2e-. How do I get the molarity of H2C2O4? PLEASE HELP

*October 11, 2010*

**ap chemistry**

A titration. 12.46 mL of KMnO4 are titrated with 25 mL of H2C2O4. The half reaction is 2H2O+H2C2O4 ARROW 2H2CO3+2H+2e-. How do I get the molarity of H2C2O4? PLEASE HELP

*October 11, 2010*

**chemistry**

Calculate the molarity for 25mL of H2C2O4 in a titration with 12.46mL of KMnO4

*October 11, 2010*

**Chemistry**

Assignment Calculate the pH, pOH, [H+], and [OH] for each of the following solutions. Show all work. (10 Points) Solution Composition of Starting Materials 1 0.10 M acetic acid 2. 5 mL 0.10 M acetic acid + 5 mL wa 3 1 mL 0.10 M acetic acid + 99 mL water 4 5 mL...

*October 11, 2010*

**communication**

the answer is c

*October 7, 2010*

**Physics**

rry leaves home at 4:07 and runs at a constant speed to the lamppost. He reaches the lamppost at 4:11, immediately turns, and runs to the tree. Larry arrives at the tree at 4:22. What is Larry's average velocity during his entire trip, if the lamppost is 363.0 m west of ...

*October 5, 2010*

**algebra word problem**

the difference between 2 numbers is 24. find the numbers if their sum is 88

*October 4, 2010*

**chemistry**

50.0 mL of water is heated from 60 C to 85 C. How much heat was absorbed by the water sample in joule Can anybody help me understand the process or rules to figuring this out? Thanks

*October 3, 2010*

**ap chemistry**

At normal temperature and pressure, air has a density of 0.001184 g/mL. What is the mass of air in a room that is 3.74 m by 3.45 m by 3.93 m? Answer in units of kg.

*October 1, 2010*

**ap chemistry**

Th solution has a density of 1.049g/mL and only 40% of the solution is acetic acid

*October 1, 2010*

**ap chemistry**

i came up with the answer of 419 g

*October 1, 2010*

**ap chemistry**

Calcu- late the mass of pure acetic acid in 440 mL of this solution at 20 C. Answer in units of g.

*October 1, 2010*

**Chemistry**

How many molecules of Cl2 would be formed from the reaction mixture that produces the greatest amount of products? Consider the following reaction: 4HCl(g)+ O2(g)to 2H2O +2Cl2(g)

*September 28, 2010*

**Math broadmoor**

1 2 3 4 5

*September 23, 2010*

**Accounting**

It is stand accounting procedures, or GAAP, to make an adjusting entry to remove the current year’s principle from the long-term liabilities. This entry reduces the long-term liabilities and increases the current liabilities. You are the bookkeeper for Biker’s ...

*September 20, 2010*

**Physics**

A jetliner can fly 6.50 hours on a full load of fuel. Without any wind it flies at a speed of 2.15 102 m/s. The plane is to make a round-trip by heading due west for a certain distance, turning around, and then heading due east for the return trip. During the entire flight, ...

*September 19, 2010*

**math**

describe a real life situation that can be represented by the following: A - (B U C) The U is a union symbol

*September 17, 2010*

**Math**

write 128 in each of the following bases A) five B)two C)twelve

*September 17, 2010*

**Math**

Where do the parentheses go in this equation? 8+3x6-4-1=13?

*September 17, 2010*

**chemistry**

2408

*September 15, 2010*

**math**

i need help on doing 442 mi in 8.5 hr and i don't know how to do it can you help me?

*September 14, 2010*

**Physics**

at what velocity would a snowball melt before it hit the wall at 32 degrees?

*September 14, 2010*

**Math**

call your tutor rather than trying to get someone else to do your course work for you

*September 14, 2010*

**health**

Case Study â€“ Memorial Health System CPOE Implementation Identify at least five indicators of project failure that manifest themselves in this case study. 2. For each of those indicators, describe what you might have done differently to eliminate or minimize ...

*September 13, 2010*

**health**

this is the case study and instead of the landor one i put lack of involvment Case Study â€“ Memorial Health System CPOE Implementation Memorial Health System is an eight-hospital integrated health care system in the Midwestern United States. The health system ...

*September 13, 2010*

**health**

Identify at least five indicators of project failure that manifest themselves in this case study. Are these right ? these are a few i have came up with: organized inertia lack of clarity of pupose lack of landor project status report insufficient leadership support

*September 13, 2010*

**Science **

in plants the process that happens when sugars break down and give off energy is called

*September 8, 2010*

**Science**

Why do we name hurricanes?

*September 7, 2010*

**Science**

Why do we name hurricanes?

*September 7, 2010*

**math**

xy = 8 y = x + 2

*September 6, 2010*

**math**

solve algebraically x^2 - 2y^2 = 11 y = x + 1

*September 6, 2010*

**math**

simplify 3sqrt-1/8

*September 5, 2010*

**Division**

3y-18/35 divided by y-6/15y

*September 5, 2010*

**math**

You make $ 90000 a year, and you get a 10% raise. Your new salary is $ .??? The next year you get a 10% cut. Your new salary is $ ????. That is ??? % less than your initial salary. How would I go about solving this??

*August 26, 2010*

**college physics**

double the height of H

*August 24, 2010*

**math**

make A 14 dot array that has exactly 2 rows

*August 19, 2010*

**Algebra II**

Two algebra II questions... simple, i believe? give a numerical example to show that subtraction is not commutative. and give a numerical example to show that subtraction is not associative. thanks(:

*August 18, 2010*

**Physics**

A scientist has devised a new method of isolating individual particles. He claims that his method enables him to detect simultaneously the position of a particle along an axis with a standard deviation of 0.12 nm and its momentum component along the axis with a standard ...

*August 16, 2010*