# Posts by J

Total # Posts: 1,013

**Science (Chemistry**

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*October 11, 2011*

**Math**

Construct a grouped frequency distribution for the following 28 scores using a class width of 4: 64 63 58 46 52 62 47 49 56 47 43 41 45 51 60 62 51 61 50 55 56 53 54 58 48 48 58 46

*October 10, 2011*

**physicsssss**

1- d= 270 2- speed= 73

*October 9, 2011*

**physics**

-2.7 cm/s

*October 9, 2011*

**Physics 1**

A mass of 5.2 kg lies at the top of a frictionless incline. It is inclined at an angle such that the normal force on the mass is 29 Newtons. If the length of the incline is 78 meters and the mass is originally at rest at the top of the incline and then released, how long does ...

*October 4, 2011*

**Physics 1**

A mass of 5 kg lies on a frictionless, horizontal floor. A force of 135 Newtons is applied to the mass at an angle above the positive x axis and a force of 14 Newtons is applied to the mass at an angle of 22.8 degrees below the negative x direction (see sketch). If the angle ...

*October 4, 2011*

**chemistry**

What is the specific heat capacity of a metal if it requires 176.1 J to change the temperature of 15.0 g of the metal from 25.00°C to 30.00°C?

*October 4, 2011*

**simplify**

23.68 ÷6.4 3.7

*September 28, 2011*

**math**

three men and their wives were given $5400. the wives together received $2400. sue had $200 more than jan, and ellen had 200 more then sue. who was married to whom?

*September 28, 2011*

**math**

a box of munchkins contains chocolate and glazed donut holes. if Gloria ate 2 chocolate , then 1/11 of the remianing munchkins would be chocolate. if she added 4 glazed to the box, 1/7 of the box would chocolate. how many munchkins are in the original box?

*September 28, 2011*

**math**

peg spends $7.50 a week for grapefruit. When grapefruit are out of season, she gets 1 fewer grapefruit than when they are in season. If the price decreases by $3 per dozen in season, how many dollars will it cost her to buy a dozen grapefruit out of season?

*September 28, 2011*

**Physics help!**

F= ma= Tension-Weight ma+Weight=Tension (4125kg)(0.0300 * 9.8)+ (4125kg)(9.81)=Tension Calculate and this will give you the answer for maximum force. For part (2) You have to subtract them (ma-weight)

*September 26, 2011*

**geometry**

This circle has a circumference of 56. What is the radius of the circle?

*September 21, 2011*

**hw help**

420

*September 13, 2011*

**math**

describe all the numbers when rounded to 312,000

*September 8, 2011*

**MATH**

USING AM IMAGINARY FIGURE OF $19,250.00 AS AN ANNUAL INCOME FIGURE, HOW MUCH MONEY COULD YOU SAVE A YEAR IF YOU BUDGETED HALF OF 2.4%?

*September 7, 2011*

**math**

You have 2 floors, and there are 14 steps inbetween the two floors. you have a cat that can get to the top by either taking one step at a time or two steps. ( at one time going up the cat can take both one or two steps). How many possible combinations are there for the cat to ...

*September 2, 2011*

**geometry**

Given ABCD, solve for x.

*August 30, 2011*

**geometry**

Line e bisects line xy at m and divides line xy into two equal parts. name a pair of congruent segments.

*August 24, 2011*

**chemistry**

sorry. The reaction is: 2 NO(g) + Cl2 ---><--- 2NOCl deltaH is the heat of reaction deltaS is the change in entropy T is temperature in kelvin deltaG is a direct measure of spontaneity DeltaH (kJ/mol) 2NO= 90.29/mol DeltaH (kJ/mol) Cl2= 0 DeltaH (kJ/mol) 2NOCl= 51.71/mol...

*August 1, 2011*

**chemistry**

Gibbs free energy What is the equilibrium constant at 25 C? deltaG= deltaH - (T(K)+deltaS) deltaS= -121.1 deltaH= -77.36 so at 25 C deltaG = -77.36 - (298*(-121.1)) deltaG ~ 3.6*(10^4) so my question is: what *is* the equilibrium constant, or perhaps more accurately, how does ...

*August 1, 2011*

**rate of reaction (formatted repost)**

I can't get my table to line up so I've surrounded the values in curly brackets. Experiment [SO2]i [O2]i IRD O2 {1} {0.05} {0.05} {7.3*[10^(-2)]} {2} {0.10} {0.05} {2.9*[10^(-2)]} {3} {0.10} {0.15} {2.6*[10^(-1)]} {4} {0.12} {0.12} {?????????????} so overall oreder is ...

*July 20, 2011*

**rate of reaction**

What is the initial rate of *appearance* of SO3(g)? a reaction and table are given: reaction: 2S02(g)+O2 -------> 2 SO3(g) Table note: i= initial, IRD= initial rate of disappearance; concentrations given in molarity (M) IRD given in M/s. Experiment [SO2]i [O2]i IRD O2 1 0....

*July 20, 2011*

**Social STUDIES**

Deez nutz

*July 7, 2011*

**math**

Express the volume of a rectangular solid (box) whose height, width and length are x,2x and 3x, respectively, as a function of its width.

*July 1, 2011*

**Psychology**

While all four are definitions of a mental disorder, the correct answer is D.

*June 28, 2011*

**physics**

a driver releases an air bubble of volume 2.0 cm^3 from a depth of 15 m below the surface of a lake where the temperature is 70C.

*June 21, 2011*

**chemistry**

13.88 mol oxygen

*June 3, 2011*

**Education**

So are the answers B, and D

*May 9, 2011*

**Chemistry**

121 atm

*May 2, 2011*

**chemistry**

Is there a relationship between HOMO & LUMO and bonding & antibonding? Explain.

*April 18, 2011*

**PHYSICS**

Its actually FFTF, thanks for the help

*April 15, 2011*

**PHYSICS**

A) As a wind instrument warms up, the resonant frequencies of the instrument tend to slightly decrease. B) If the air in a concert hall warms up, the resonant frequencies of the string instruments will change precisely the same as the resonant frequencies of the wind ...

*April 15, 2011*

**calculus**

A rectangular box is to be constructed from two different materials. The box will have a square base and open top. The material for the bottom costs $4.25/m2. The material for the sides costs $2.50/m2. Find the dimensions of the box with the largest volume if the budget is $...

*April 9, 2011*

**math**

A circular pie with a diameter of 9.8 inches is cut into 7 equal slices. What is the approximate area of one slice?

*March 31, 2011*

**math**

Denisha used 9 balls of clay and 16 straws to make a solid pyramid.how many faces does the solid have?

*March 29, 2011*

**physics**

An object traveling 200 feet per second slows to 50 feet per second in 5 seconds. Calculate the acceleration of the object.

*March 28, 2011*

**math**

What is the degree of the 3rd angle if the other two are 68 degrees?

*March 28, 2011*

**Math**

20(1/5n - 3/4) + 9n

*March 22, 2011*

**physics**

0.35

*March 20, 2011*

**Financial Management**

500

*March 6, 2011*

**coordinate geometry**

all i gotta do is find slope & y intercept this is 6th math

*March 3, 2011*

**coordinate geometry**

some smart person solve thiss ;] y-18x+18=4 or help me im confused

*March 3, 2011*

**chemistry**

The simple rule “Like dissolves like” is often used to describe the solubility of a substance in different solvents. Write a short paragraph discussing your evidence for this rule. Include in your discussion where you think this rule works best and where it seems to ...

*February 27, 2011*

**Chemistry**

density decreases and the molarity decreases

*February 22, 2011*

**Physics**

A 55.0 kg girl is roping through the top of a tiny tree. She quickly swings down from her 12.0 m high perch and grabs a 21.0 kg dog as she swings. They barely swing back up to a tree limb. How high is this tree limb?

*February 15, 2011*

**physics-mechanics**

A high-speed test track for cars has a curved section — an arc of a circle of radius R = 1440 m. The curved section is banked at angle a = 19.1 degrees from the horizontal to help the cars to stay in the road while moving at high speeds. The acceleration of gravity is 9.8...

*February 12, 2011*

**Math**

Need help solving this problem. If there's an equation at the end, need help in how to solve that also. Compounded interest problem. Principal $825. Rate 4%. Compounded Annually. Time 10 years.

*February 9, 2011*

**j**

What were the factors that played a significant role in the collapse of Russian control over Eastern Europe?

*February 7, 2011*

**arithmetic**

How do I solve these questions? 3 1/3 - 2 2/5= 2.75 + .003 + .158 = 7/20 is equal to ? What is the value of the expression 2x2+ 3xy – 4y2 when x = 2 and y = - 4? 16x - 8 = If 2x – 3(x + 4) = - 5, then x = – 3(5 – 6) – 4(2 – 3) =

*February 3, 2011*

**Calculus**

find lim f(x) - lim f(x) x->infinity x->-infinity if f(x)=ln (x+sqrt[x^2+a^2])/(x+sqrt[x^2+b^2]) a and b are real numbers

*February 2, 2011*

**Calculus**

find lim f(x) - lim f(x)

*February 2, 2011*

**Physical Science**

If a person is traveling at a rate of seventy five miles per hour in a straight line, how far would they travel in three seconds?

*February 1, 2011*

**Physics**

A watch manufacturer claims that its watches gain or lose no more than 8s in a year.

*February 1, 2011*

**comm**

extra is a adjective right???

*January 18, 2011*

**comm**

envelope-adverb credit-adjective spent-adverb

*January 18, 2011*

**comm**

came over- adjective frowning- adverb

*January 18, 2011*

**comm**

this is the reason why getting a credit card at a young age is not a great idea because you get anxious and want to buy a lot of things when you know you don't have the money.

*January 18, 2011*

**comm**

yes i do need help

*January 18, 2011*

**comm**

i need help identify adjectives and adverbs:My dad added me as an extra card holder on his credit cards. I was very excited that I could purchase products now and pay for them later. I didn’t realize how much money I was spending. He came over to my house recently, ...

*January 18, 2011*

**physics**

Okay, I have an example problem that I'm trying to solve that comes with the answer; I'm just trying to figure out what to do. A man jogs at a speed of 1.8 m/s. His dog waits 2 s and then takes off running at a speed of 4 m/s to catch the man. How far will they have ...

*January 15, 2011*

**Conductivity**

you are amazing!

*January 12, 2011*

**history**

Who were some of the original Texas Wildcatters?

*January 6, 2011*

**physics pleaaaaaaaaaaaaaaaaaaaaaaaaaaaaaase I need**

Consider a square ABCD of side 10cm and total mass 10kg. Let O be the center of the sqaure. We cut a square of corners O and C. Find the central mass of the obtained shape after removing the small cutten sqaure. I appreciate your help. thank you

*January 6, 2011*

**math/ physics**

Consider a square ABCD of side 10cm and total mass 10kg. Let O be the center of the sqaure. We cut a square of corners O and C. Find the central mass of the obtained shape after removing the small cutten sqaure. I would appreciate your help. thank you

*January 6, 2011*

**algebra**

2y-6x=8 2y=6x+8 y=3x+4 please explain this to me

*January 5, 2011*

**math**

i was shown example: x+6=-5 6=-5 6--5=x x=-11 please explain to me how they got this

*January 5, 2011*

**world history**

What are some characteristics of Greek civilizations?

*December 14, 2010*

**Physics**

TH/TC=(1)/(1-0.308)

*December 10, 2010*

**Math Finite**

0.2442

*December 9, 2010*

**physics**

your so stupider than me if you donts know hows to do this problam!

*December 6, 2010*

**Europe**

what is the most important advantage og having germany in the European Union?

*December 2, 2010*

**Chemistry**

-q = dH ( dH = change in enthalpy Kj/mol) Use q=mc(Tf-Ti) and then convert to deltaH q=mc(Tf-Ti) q =? c= 4.814 J/g*C use specific heat of water since its in aqueous sol and we are not told differently m= total mass= mass KBr + mass water mass KBr= 5.0 g *mass of water from ...

*December 2, 2010*

**math**

Hmm 12 is already an even number! Hence you should not count 12 twice, therefore answer should be 7/15. :)

*November 27, 2010*

**social studies**

Hi majenta, In my view a thesis statement is only good if it is properly justified. In this case, you have to clarify what you mean by "important" - which may be subjective (different people may interpret it differently) as well as rather broad. So like what I think ...

*November 27, 2010*

**holy name university**

Hi january, Dalton's Law of partial pressures states that P(total) = P(1) + P(2) + P(3) +....+ P(n) where 1, 2 and 3 are gases in the mixture. So applying the law 150kPa = 100kPa + 24kPa + P(oxygen) Hope I helped! (: -J

*November 27, 2010*

**chemistry**

Oops, sorry, my apologies for typing in caps. Was just trying to point that out. :)

*November 26, 2010*

**chemistry**

Hi faye, Alright so we want to prepare a 800ml solution of 0.15M concentration. So first we calculate the amount of Ca(OH)2 **NOTE: SHOULD NOT BE CA(OH) COS +2 CHARGE OF CA2+ IS NOT BALANCED! CA(OH)2 IS A SOLID AND NOT AN ION, HENCE THE COMPOUND CANNOT HAVE AN OVERALL CHARGE...

*November 26, 2010*

**Chemistry**

Hi Lindsay, Alright, to begin with, since this is an organic compound, we identify the functional group. [-C(=O)-NH- means its an amide] So when you hydrolyse an amide, you are breaking the (amide) bond between C=O and N-H, and you add water because its a hydrolysis (OH- goes ...

*November 24, 2010*

**chem class**

Hi laney, For this question, it would be appropriate for you to ask yourself.. what is present in the solution after mixing? KOH is a strong basic salt while HCL is a strong acidic salt. KOH + HCL --> KCL + H2O Note that amount of KOH = HCL = 0.125 X (50/1000), so there is ...

*November 24, 2010*

**chemistry**

Hi roseanne, First, we write out the equation when MX2 dissolves in water (or a suitable solvent): MX2 --> (reversible arrow) M2+ + 2X- So Ksp = [M2+][X-]^2 Solubility would refer to the concentration of an ion produced in 1:1 ratio with the original solid. In this case, we...

*November 24, 2010*

**Chem, LAST ONE PLEASE HELP!**

Hey Tara, Hmm, I'm not too sure about this question, but I'd guess it has something to do with the following formula: G = G(not)+ RTlnQ So basically G(not) = -67.4 kJ R= 0.008314 kJ mol^-1 K^-1.(molar gas constant)(Note that units must be kJ to match up with the G(not...

*November 24, 2010*

**physics**

Hi sweetie, As a coconut is falling down, the only force acting on it is the gravitational force (its weight) if you neglect air resistance. So as it is accelerating as it falls, velocity ______. P.E. of coconut = mgh, where m = mass of coconut, and h = height of coconut above...

*November 24, 2010*

**physics**

Hi sweetie, momentum = mass (kg) X velocity (m/sec). So for 1) At rest, velocity = 0m/sec. So momentum should be.... (Apply formula above) [Ans:0 kgm/sec] for 2) At that final state, velocity = 30m/sec. So momentum should be.... (Apply formula above) [Ans: 90,000kgm/sec] for 3...

*November 24, 2010*

**chemistry**

Hi Tara, To find out if a reaction is spontaneous, we calculate E(cell). If E(cell)>0, reaction is spontaneous. If E(cell)<0, reaction is not spontaneous. If E(cell)=0, reaction will proceed until equilibrium is established. So in this case, E(cell) = E(reduction)-E(...

*November 24, 2010*

**maths**

Oops sorry! I realised that I also made a mistake near the end. When I said "...Therefore, 24x=98cm.." I meant 14x (Not 24!) = 98cm. =)

*November 24, 2010*

**maths**

Hi aisha, Let's start with formulating an algebriac expression for the perimeter. We know that perimeter of rectangle = 2(length) + 2(width). Since we don't know length or width, we let x be the width of the rectangle. Hence length = 5x-3 [because length = (5 X width...

*November 24, 2010*

**chemistry**

Hi Tara, Alright, by convention, we usually write [Oxidation]/[Reduction]in notation. Hence, the oxidation half-cell is the Cr/Cr3+ half-cell while the reduction half-cell is the Ni2+/Ni half-cell. [Alternatively, you can compare E(not) values such that the half-cell with the ...

*November 24, 2010*

**chemistry**

That comes from multiplying 3X10^-8 and 0.0385 when we expand 3X10^-8(0.0385-x).

*November 23, 2010*

**chemistry**

Hiya, From what you said it seems that you understand everything up till "x = [H+]= 3.4 x 10^-5 M" So we know that 3X10^-8 = x^2/(0.0385-x) Bring (0.0385-x) over to the left hand side, Hence 3X10^-8(0.0385-x) = x^2 Then we expand the left hand side, 1.155X10^-9 - ...

*November 23, 2010*

**HUM176**

Newspapers, once available only in print, have evolved into 24-hour multimedia operations. In addition to newspapers, briefly describe the evolution of movies, television, Internet, books and magazines, and media companies throughout the last century.

*November 21, 2010*

**algebra**

(6*5)/3 is this a true sentence

*November 21, 2010*

**Probabilities**

1.) two marbles are drawn without replacement from a bowl containing seven red, four blue, and nine yellow marbles. what is the probability that at least one is red? 2.)a card is drawn from a standard deck of 52 cards. what is the probability that the card is neither a four or...

*November 9, 2010*

**Probabilities**

1.) two marbles are drawn without replacement from a bowl containing seven red, four blue, and nine yellow marbles. what is the probability that at least one is red? 2.)a card is drawn from a standard deck of 52 cards. what is the probability that the card is neither a four or...

*November 9, 2010*

**AP Chem**

66 kJ/mol

*November 7, 2010*

**chemistry**

could someone please still explain? and explain how the 4.74 pH was found? thanks

*November 7, 2010*

**chemistry**

couple someone please still explain? and explain how the 4.74 pH was found? thanks

*November 7, 2010*

**Social Studies**

name if the following involve, seperation in powers, checks and balances, judicial review, federalism, or some combination of these principles, and say why A) the state law requires that a prayer be said each day in public schools. The courts rule that law wiolates a first ...

*October 31, 2010*