Monday

September 26, 2016
Total # Posts: 455

**Chemistry**

The toxic metal cadmium Cd2+ has a tendency to complex with as many as 4 Cl- ions. The complexation reactions can be written as: Cd2+ + Cl- ---> CdCl+ ``````` log Kf,1 = 1.98 Cd2+ + 2Cl- ---> CdCl20 `````` log Kf,2 =2.60 Cd2+ + 3Cl- ---> CdCl3- `````` log Kf,3 = 2.40 ...

*September 15, 2016*

**chemistry**

The problem is as follows: The toxic metal cadmium Cd2+ has a tendency to complex with as many as 4 Cl- ions. The complexation reactions can be written as: Cd2+ + Cl- ---> CdCl+ log Kf,1 = 1.98 Cd2+ + 2Cl- ---> CdCl2^0 log Kf,2 =2.60 Cd2+ + 3Cl- ---> CdCl3- log Kf,3...

*September 15, 2016*

**physics**

Sally travels by car from one city to another. She drives for 29.0 min at 63.0 km/h, 37.0 min at 32.0 km/h, and 14.0 min at 26.0 km/h, and she spends 14.0 min eating lunch and buying gas.

*September 13, 2016*

**math**

Ness won $2400000 in a state lottery. After paying 39% of her winnings to taxes, she invested some of the money into an account earning 4.8% interest and the rest into an account earning 3.9% interest. If the total interest earned was $65655, how much did she invest into each ...

*September 7, 2016*

**Math**

How to simplify rational expression 4x-2y divided by -2x-y

*August 3, 2016*

**Economics / Finance**

What is the distinguishing feature of the limited partnership? (a)The partners run the business together and share all profits and losses according to the ...

*July 25, 2016*

**pre cal**

The vector u = (4300, 5200) gives the number of units of two models of laptops produced by a company. The vector v = 1800, 1200 gives the prices (in dollars) of the two models of laptops, respectively. Identify the vector operation used to increase revenue by 5%. (the // ...

*July 14, 2016*

**science**

Here are some examples of molecules: Cl2, CO2, SO2, and CF4. Each of these is related in that they're all bonded covalently. Which of these is a covalently-bonded molecule also? A. He atoms B. K2S C. BaBr2 D. P2O4

*June 29, 2016*

**Physics**

The earth is realtive to space? I don't know how they measure the speed earth is traveling. But the rocket would be relative the to same measurement as the planet's speed.

*May 28, 2016*

**Physics**

If our planet is travelling at 10000 mph (just using hypothetical numbers) and you launched a rocket into space at 10000 mph (ignoring the planets rotational speed to keep this simple) on the same exact path the planet is moving, would the rocket be moving at 20000 mph in space?

*May 28, 2016*

**Geometry**

What is the height of a pole standing 20 feet from the base of pole and measure the angle of the elevation to the top of the pole to be 54 degrees what's the height of the pole

*May 22, 2016*

**Pre-Calc College**

so the maintenance level is 2.1 mg?

*May 16, 2016*

**Algebra**

If f(x) is a linear function such that f(4) = 3, with a slope of 1/2, what is the equation of f(x)?

*April 27, 2016*

**SS**

^Note: I'm not saying these are AP U.S. History questions - they're clearly easier. It's just that I don't remember all details about U.S. history.

*April 26, 2016*

**SS**

1. A 2. C 3. A 4. C 5. A 6. D 7. C 8. B 9. C 10. D Disclaimer: I took APUSH a few years ago, and I'm a Biochem major.

*April 26, 2016*

**Maths**

There are five sand which fillings - ham, cheese, tomato, lettuce and totally plain. How many combinations? I make 11. Ham, h & c, h & t, h&l; cheese, c & t, c & l; tomato; lettuce, l & t; sandwich with no filling. Total is 11. Some doubt in the family with this! Many thanks, ...

*April 13, 2016*

**Chemistry**

Small amounts of chlorine gas can be gener- ated in the laboratory from the reaction of manganese(IV) oxide with hydrochloric acid: 4 HCl(aq) + MnO2(s) → 2 H2O(l) + MnCl2(s) + Cl2(g). What mass of Cl2 can be produced from 41.8 g of MnO2 with an excess of HCl(aq)?

*March 30, 2016*

**Chemestry**

What is the volume of 454 grams of Ferrous sulphate heptahydrate?

*March 18, 2016*

**Algebra**

factor a^2+10a+24 t^2+4t-45

*March 11, 2016*

**Algebra**

Factor 10w squared minus 19 minus 15

*March 9, 2016*

**Algebra**

Factor 3g squared - 7g +2

*March 9, 2016*

**Algebra**

the length of a rectangle is 4cm more than the width of the rectangle. If you increase the length by 8cm and decrease the width by 4cm, the area will remained unchanged. Find the original dimensions

*February 22, 2016*

**Algebra 1**

You trimmed a large square picture so that you could fit it into a frame. The area of the cut picture is 20 square inches. What is the area of the original picture?

*February 17, 2016*

**Math**

4 pennies, 2 nickels, 3 dimes in a pocket. If two are coins are chosen, what is the probability that both are dimes?

*February 11, 2016*

**ACT Prep**

Question:So,far Michael has earned the following scores on five 100-point tests this semester: 72, 94, 85, 83, 97. What score must he earn on the sixth 100-point test of the semester if he wants to make an 88 point average for the six tests? Answer Choices A. 88 B. 100 C. 97 D...

*February 3, 2016*

**chemistry**

can someone explain to me what happens when zinc and copper sulfate react? I know its a redox reaction and it gives off heat making it exothermic, but don't know whats actually happening in that reaction. can someone explain to me that reaction?

*January 12, 2016*

**maths**

you mean x=sqrt3 or 9, not u

*December 29, 2015*

**Physics**

Compute the initial upward acceleration of a rocket of mass 1.5 ✕ 104 kg if the initial upward force produced by its engine (the thrust) is 2.7 ✕ 105 N. Do not neglect the weight of the rocket. Pleas tell me the steps, I've tried getting the acceleration and ...

*December 15, 2015*

**Chemistry**

Suppose we had mixed 52.37 mL of 1.00 M HI solution with 25.42 mL of 1.00 M KOH solution, and measured a heat of reaction of -1.52 kJ. What is ΔH for this reaction, in kJ? Assume that all solutions have the same density as water (1.00 g/mL).

*December 11, 2015*

**TECH MATH**

A factory creates wooden beads used for various arts and crafts projects. One particular type of bead is in the shape of a cube. Each side of the bead is 0.25 inches long. A cylindrical hole with diameter of 0.12 inches is cut through the bead so that string can be threaded ...

*November 23, 2015*

**math**

A cyclinder cooling tank has an outside diameter of 6.00 ft. the wall on all sides are 5.00in thick and the tank is 10.0ft tall. how many gallons of water will this tank hold?

*November 14, 2015*

**Statistics**

I know don't know if this right P(X)<115)= 12.1 (115-mean) how do I get the mean or is there a formula that can help me solve this? A population of line voltages has a standard deviation of 1.20 volts. What value would the mean line voltage have to be so that 12.1% of ...

*October 5, 2015*

**Please help**

A rectangular picture frame has a perimeter of 58 inches. The height of the frame is 18 inches. What is the width of the frame? Please help show work and help answer thanks

*September 25, 2015*

**Algebra**

A diver begins at sea level and descends vertically at a rate of 2 1/2 feet per second. How long does the Diver take to reach -15.6 feet?

*September 22, 2015*

**Algebra**

K2 is11,194 feet higher than Mt. Kenya. Write and solve an equation of Mt. Kenya. Please hep with this 9ne thanks

*September 22, 2015*

**Algebra **

A hot air balloon begins its descent at a rate of 22 1/2 feet per minute. How long will it take for the balloons elevation to change by -315 feet?

*September 21, 2015*

**algebra**

Assume that S/A = 7.0, D/A = .40, N/E = .80 and A = D + E. Solve for N/S.

*September 9, 2015*

**Math**

Given that: 4x – y + 9 = 0 and 3y – 2x = 7, solve for x. does x=-2?

*September 9, 2015*

**Math**

Two planes leave New Orleans at the same time. Plane A heads north and Plane B heads south. After 4 hours and 15 minutes, the two planes are 4568.75 miles apart. Also, Plane A is traveling 53 mph faster than Plane B. At what speeds are the two planes traveling at? How far did ...

*September 2, 2015*

**Intro Chem**

Determine the freezing point of an aqueous solution containing 10.50 g of magnesium bromide in 200.0 g of water.?

*August 30, 2015*

**chemistry**

How many grams of table sugar (C12H22O11) will be needed to make 3.5 L of a 11.5 M solution?

*July 27, 2015*

**chemistry**

in our notes for strengths of acids and bases it says that you could add a strong/weak acid with a strong/weak base and it will give you a low, medium or high delta h. so wouldn't acids and bases be related to thermochemistry?

*July 16, 2015*

**Chemistry**

Calculate the sodium ion concentration when 50.0 mL of 2.0 M sodium carbonate is added to 100.0 mL of 3.0 M sodium bicarbonate.

*May 27, 2015*

**Math**

You are considering two mutual funds for your investment. The possible returns for the funds are dependent on the state of the economy and are given in the accompanying table. State of the Economy | Fund A | Fund B Good | 20% | 40% Fair | 10% | 20% Poor | -10% | -40% You ...

*May 24, 2015*

**IT/235 - IMAGE EDITING AND IMPLEMENTATION**

How would the photography affect the day-to-day store operations under each model?

*May 11, 2015*

**chemistry**

Determine the hydroxide ion concentration in a solution that is 0.0004 M HCl. Answer in units of M. I have no idea how to start, I just need to know what I need to solve for and hoe to set it up, I know the formula pOH^-=-log[OH^-] I just don't know where to plug things in...

*April 16, 2015*

**math**

Please show your work. Tutors will not do your homework for you. Please show your work for any question that you are posting.

*March 29, 2015*

**math**

In the triangles, we have XY = 2AX = 2YB and AZ/ZC = 2/3. Find the ratio of the area of triangle YBC to the area of triangle ZYC.

*March 29, 2015*

**math**

The function f(x) = cx/2x+3 satisfies f(f(x))=x for all real numbers x\= -3/2. Find c.

*March 26, 2015*

**math **

A rectangle has an area of 400 cm^2. If the rectangle is a square, what is its perimeter?

*March 26, 2015*

**Math**

Suppose you have a cache of radium, which has a half-life of approximately 1590 years. How long would you have to wait for 1/5 of it to disappear?

*March 26, 2015*

**math**

But what about how far he is from the lightning?

*February 27, 2015*

**math**

During a severe thunderstorm, Tim saw a flash of lightning and then six seconds later heard a clap of thunder. The speed of sound is 1088 ft/sec. How far is Tim from the lightning? Nearest Thousand Feet.

*February 27, 2015*

**Algebra**

Use algebra tiles to determine if 2(x +3) is equivalent to 2x +3. Explain your answer thanks

*January 21, 2015*

**Algebra please help**

Lisa evaluated the expressions 2x and x squared for x=2 and found that both expressions were equal to 4. Lisa concluded that 2x and x squared are equivalent expressions. How could you show. Lisa that she is incorrect? Please help explain thanks

*January 21, 2015*

**Pre calc**

A boat is going 30 mph. It's direction is 100 degrees east of north. The water current is 15 mph and has a direction of 22 degrees east of north. Find the magnitude, and direction of boat.( with water current)

*January 20, 2015*

**Pre calc**

A boat is going 30 mph with a direction of 100 degrees east of north. The water current is 15 mph with a direction of 22 mph. What is the magnitude of boat and direction

*January 20, 2015*

**Algebra 1**

The town of Rayburn received 6 more inches of snow than the town of Greenville. Let g represent the amount of snow in Greenville. Write an algebraic expression to represent the amount of snow in Rayburn.

*January 14, 2015*

**Algebra 1 **

Jill, Meg and Beth are sisters. Jill is 2 years younger than Meg. Beth is half as old as Meg. Let m represent Meg'a age. Write 2 other algebraic expressions based on the situation. Tell what each expression represents, and what the variable stands for in each expression. ...

*January 14, 2015*

**algebra 1**

A very old vending machine accepts only nickels (n) and dimes (d). Candy costs up to $0.50, but sometimes the machine will dispense candy without any coins being inserted into the machine. Which inequality shows all of the ways to obtain a candy bar from the machine?

*January 13, 2015*

**Algebra**

Find a if the point (3,a) is on the line that passes through (-2,7) and (5,-3).

*December 31, 2014*

**P.E. help please**

45% of 10 is 4.5 So the answer is c Multiply your answer by 10 and the number your trying to get the % from by 10 as well 10x10=100 4.5x10=45 Percent is a calculation of part of 100. And in this case you make the "10" a 100 by multiplying it by 10

*December 3, 2014*

**statistics**

Well if of 100 students there is 70 boys, and only 70% of the boys are in sports, all you need to do is find 70% of 70. Which is 49. 70 x 0.07= 4.9 4.9x10=49

*December 3, 2014*

**Chemistry**

If a solution contains 0.65mol of OH−, how many moles of H+ would be required to reach the equivalence point in a titration?

*November 16, 2014*

**math**

a man 5 ft tall casts a shadow of 6 ft. The angle of elevation f the sun is?

*November 15, 2014*

**Physics**

A puck of mass 0.165 kg, initially resting on ice, is hit by a stick to gain a speed of 32.0 m/s and then slides 25.0 m to lose 5.00% of its kinetic energy. (a) What is the work done on the puck by the stick? (b) What is the kinetic friction coefficient between the ice and puck?

*October 11, 2014*

**Business math**

Order for 620 dresses from China, cost is $40 a gown, markup based on selling is 76%, what is the selling price of each gown?

*September 26, 2014*

**Chemistry**

1 ersk * ( 100 ed / 12 ersk ) * ( 10 ebb / 9.5 ed ) * ( 1 zum / 5 ebbs) Calculate it yourself

*September 22, 2014*

**algebra**

If only natural gas is hit, the income will be $140,000. If nothing is hit, there will be no income. If the probability of hitting oil is 1/40 and if the probability of hitting gas is 1/20, what is the expectation for the drilling company?

*September 10, 2014*

**physics**

A rifle with a muzzle velocity of 480 m/s shoots a bullet at a target 45.6 m away. How high above the target must the rifle barrel be pointed to ensure that the bullet will hit the target? Neglect air resistance.

*September 7, 2014*

**chemistry**

Nevermind, I did it, I should be paying you for all this help ;) I had to take other pk 2.35+log10(102) =4.35

*August 26, 2014*

**chemistry**

9.78+log10(1/102) =7.77 sounds good?

*August 26, 2014*

**chemistry**

thank you I'm looking into this albeit totally lost atm

*August 26, 2014*

**chemistry**

glycine and lysine, have the following values of the relevant acid dissociation constants (pKa) glycine, pKa=2.35 lysine,pKa=10.79 For an aqueous solution of glycine alone, calculate the value of pH at which the ratio of the concentration of neutral glycine zwitterions to the ...

*August 26, 2014*

**Chemistry Help!!!!!!!!!!!!!!**

a) Carbon [He]2s²p² b) Silicon [Ne]3s²p² Hund rule -> fill from bottom to top Pauli -> first you fill orbitals with one spin and then the other ex. if you have 4 electrons in p orbitals P 11 1 1 __ __ __ p.s. if they don't delete this too

*August 26, 2014*

**chemistry**

got it! ka= 3.26*10^-3 so pKa=2.49 tnx

*August 26, 2014*

**chemistry**

A 1.11 M solution of fluoroacetic acid, FCH2CO2H, is 5% dissociated in water. Calculate the value of the pKa of FCH2CO2H. pKa: ?? I dn't even know how to strt with this

*August 26, 2014*

**chemistry**

what image? degree of polymerization is like this propylene is H2C=CH-CH3 so 3C and 6C molec. weigth (12*3)+6 = 42 g/mol n = 3.091*10^5 / 42 = 7359.52

*August 25, 2014*

**chemistry**

it's ok, that's 372 nm it's uv I got same result

*August 24, 2014*

**chemistry**

volts and eV aren't like "multiples" eV is an energy, V a potential taht's V and it's checked correct ;)

*August 24, 2014*

**chemistry**

Determine the potential (V) by which a proton must be accelerated so as to assume a particle wavelength of 0.0293 nm. ---- This is what I did, dunno if right - wavelength in meters = 2.93*10^-11 m - used DeBroglie relation to find energy lambda = h / mv, v from kinetic energy...

*August 24, 2014*

**chemistry**

Calculate the wavelength (in m) of a photon capable of exciting an electron in Li2+ from the state n= 3 to the state n=5

*August 24, 2014*

**chemistry**

Thank you!

*August 24, 2014*

**chemistry**

a) Calculate the number of moles of nitrogen dioxide, NO2, that could be prepared from 79.0 mol of nitrogen oxide and 82.0 mol of oxygen. 2NO(g)+O2(g)⟶ 2NO2(g) b) Identify the limiting reagent and the excess reagent in the reaction. What would happen to the potential ...

*August 24, 2014*

**banking**

1100

*August 2, 2014*

**chemistry**

Reaction is second order, even if your plot of 1/T doesn't give a perfectly straigth line. a) 2 b) 0.71 my reagrds to will

*July 26, 2014*

**Chemistry**

A compound of chlorine and fluorine, ClFn, reacts at about 75oC with uranium metal to produce uranium hexafluoride, UF6 and chlorine monofluoride, ClF (g). A quantity of uranium produced 3.53g UF6 and 343 mL ClF at 75oC and 2.50 atm. What is the formula (n) of the compound?

*May 26, 2014*

**Math**

Nina walked 15 yards to Paul's house. They then went hiking. Which rule shows how many yards Nina walks for every yard Paul walks? a. p=n+15 b. n=p+15 c. P=15-n d. n=p-15

*March 20, 2014*

**physics**

An X-ray tube used for cancer therapy operates at 4.04 MV with a beam current of 23.4 mA striking a metal target. Calculate the power of this beam.

*February 12, 2014*

**algebra**

x^3+4a+5a^2x^6 ascending order

*February 9, 2014*

**math**

Please, can you explain it more clearly :D please BY TONIGHT

*February 6, 2014*

**Algebra**

7. Paula is an office manager for ABC Advertising. She has been tasked with finding a copy machine that falls within a budget of $750 per month. She finds a company that will lease the machine for $275 a month. Each copy costs 4¢ and a ream of 500 sheets of paper costs $5...

*February 2, 2014*

**Algebra**

1. A firm pays $1.75 for each copy of a magazine and sells each one for $2.50. There is a fixed monthly cost of $40 for printing the publication. If the firm wants to make $550 dollars next month, how many magazines do they have to sell?

*February 2, 2014*

**Introductory to algebra**

simplify both sides of the following equations as much as possible and the solve: 4x+2-3x=4+1

*January 20, 2014*

**Biology**

Could someone please explain Endocytosis(phagocytosis, pinocytosis and receptor-mediated endocytosis) in simplest way? I do not understand

*October 23, 2013*

**calculus**

Find the area bounded by {y=x2−4 y=4−x2 • sketch the region described • determine any intersection point(s) for the curves (show work!!) • write out the integral(s) that will calculate the area • determine the area (may use a calculator)

*October 3, 2013*

**chemistry Pleae**

thankyou its meant to be propyl butanoate and sodium hydroxide

*August 22, 2013*

**chemistry Pleae**

C7H14O2 + NaOH What will this combination make? and can it be balanced?

*August 22, 2013*

**chemistry**

Dr bob they will go on different carbons, sue knows this they are called isomers, do you have a list of the isomers for this compound?

*August 21, 2013*

**Statistics**

A researcher surveyed college students to study their opinion about the proposed change in smoking rules. The researcher asked a group of 30 students: 12 of them supported the change, 13 of them did not, and 5 had no opinion. This is not a binomial model because... A. ...the ...

*July 29, 2013*