Friday

February 24, 2017
Total # Posts: 2,482

**chemistry**

A buffer is made by dissolving HC2H3O2 and NaC2H3O2 in water. Write an equation that shows how this buffer neutralizes added acid. Express your answer as a chemical equation. Identify all of the phases in the answer.

*December 3, 2012*

**trig**

A 600,000-cell bacteria culture is needed for a lab experiment, but you only could purchase 1,000 cells. If the cells double each day, exactly how long will it be before the experiment can be run? Create a model for the bacteria. If the experiment is in seven days, how many ...

*December 3, 2012*

**math**

Suppose that you are taking a course that has three exams which count for three-fifths of your grade and a final which counts for two-fifths of your grade. On your first three tests your scores on were 75, 80, and 74. To get an B in the course, you must have an average of at ...

*December 2, 2012*

**Geometry**

In triangle EFG, M<F=3(m<G), and m<E=m<F-30degree. Find the measure of each angle.

*November 28, 2012*

**Ethics & Justice Administration**

If I am looking to support my pro capital punishment theories which of the following ethical theories would best support my stance? I must use two. Absolutism, ethical formalism, utilitarianism, hedonism-stoicism, natural law, ethics of virtue, ethics of care, egoism, cultural...

*November 28, 2012*

**Physics**

Alright but does anyone know how to solve this?

*November 27, 2012*

**Physics**

Thanks for the thought anyways!

*November 27, 2012*

**Physics**

How is asking for help on a homework help site cheating?? I don't know where to start...

*November 27, 2012*

**Physics**

Two fraternities are in a tug of war. Theta Chi is pulling with a total force of 4,748 newtons to the east and Tau Kappa is pulling with a total force of 3,969 newtons to the west. What is the magnitude and direction of the resultant? Which team will win? Is it better to pull ...

*November 27, 2012*

**math**

Find the accumulated amount A, if the principal P is invested at an interest rate of r per year for t years. P = $24,000, r = 7%, t = 6, compounded monthly $ ?

*November 27, 2012*

**Physics Can you help me get started**

A 24-g ice cube floats in 180 g of water in a 100-g copper cup; all are at a temperature of 0°C. A piece of lead at 92°C is dropped into the cup, and the final equilibrium temperature is 12°C. What is the mass of the lead? (The heat of fusion and specific heat of ...

*November 26, 2012*

**math**

Find the present value of $31,000 due in 4 yr at the given rate of interest. (a) 6%/year, compounded quarterly $ ? (b) 3%/year, compounded quarterly $ ?

*November 26, 2012*

**math**

Find the present value of $31,000 due in 4 yr at the given rate of interest. (a) 6%/year, compounded quarterly $ ? (b) 3%/year, compounded quarterly $ ?

*November 25, 2012*

**math**

Find the present value of $53705.69 due in 5 yr at an interest rate of 8%/year compounded continuously. $ ?

*November 24, 2012*

**math**

Find the present value of $31,000 due in 4 yr at the given rate of interest. (a) 6%/year, compounded quarterly $ ? (b) 3%/year, compounded quarterly $ ?

*November 23, 2012*

**Math**

Find the effective rate corresponding to the given nominal rate. (Round your answer to the nearest hundredth of a percentage point.) (a) 4%/year, compounded quarterly ? % (b) 3%/year, compounded monthly ? %

*November 23, 2012*

**Math**

Find the effective rate corresponding to the given nominal rate. (Round your answer to the nearest hundredth of a percentage point.) (a) 4%/year, compounded quarterly ? % (b) 3%/year, compounded monthly ? %

*November 23, 2012*

**Drama**

I have to find a 6-8 minute monologue for my HSC and i cant find a good site to help me if anyone has any good answers please help me i need it soon!!

*November 21, 2012*

**statistics**

what is the probability of winning a lottery with 8 numbers drawn from 52 numbers (assume you buy 1 ticket)?

*November 14, 2012*

**science**

what is an artery thattakes the oxygen rich blood to the rest of the body from the heart

*November 13, 2012*

**math**

If p is an odd prime, prove that (2/p)=(-1)^[(p^2-1)/8]

*November 13, 2012*

**Chemistry**

10, 122, 299, --> 162, 5, 122, 60, 60, 188

*November 10, 2012*

**Chemistry**

Please write the balanced chemical equation for reaction the following chemical reaction ozone gas, O3, reacts with 3,3,4,4,5,5-hexanmethyl-1-hexyne, H-C≡C-C(CH3)2-C(CH3)2-C(CH3)2-CH3 to produce carbon dioxide gas, CO2 , and water gas, H2O When balancing the equation , ...

*November 8, 2012*

**physics**

A large balloon of mass 237 kg is filled with helium gas until its volume is 318 m3. Assume the density of air is 1.29 kg/m3 and the density of helium is 0.179 kg/m3. (b) Calculate the buoyant force acting on the balloon.________N (c) Find the net force on the balloon and ...

*November 7, 2012*

**calculus**

a particle is moving counterclockwise around the circular path whose equation is x^2+y^2=100 of the abscissa of the particle is increasing by 72in/sec at a point where x=8 find the rate of changeof the cordinate(y) at this point

*November 7, 2012*

**Physics**

-1.7 m/s

*November 6, 2012*

**chemistry**

If 92.75 mg of Na2CO3 is dissolved in 0.5mL of water, what would be the normality of the solution after the addition of 0.67 mL of water.

*November 5, 2012*

**english**

Baldwin uses many different writing techniques in the essay. Find instances of concrete description of a person of place, action reflection, and strong argumentative assertions. How do these techniques further his specific purposes?

*November 5, 2012*

**Biology**

In humans, W=widows peak while w=normal hair line and A=attached earlobes while a= unattached earlobes. A heterozygote in both traits reproduces with a similar heterozygote in both traits. What is the chance of any one child having the same genotype of the parents?

*October 30, 2012*

**Macroeconomics**

The graph has a SRAS going up from GDP 13.7 and 110 price level GDP 14.0 and 120 price level GDP 14.2 and 130 price level

*October 24, 2012*

**Macroeconomics**

Cannot attach graph! a. If the actual price level exceeds the expected price level reflected in long-term contracts, real GDP equals _______ and the actual price level equals _______ in the short run. b. The situation described in part (a) results in a(n) _______ gap equal to ...

*October 24, 2012*

**chem**

a new compound composed of just Hex-Nuts and bolts is formed.A 13.7 Kg sample of the new compound is separated into its component elements with the following result 3.84 kg. of hex-nuts and 9.90 kg of bolts. 1. How many hex-nuts are present in the 13.7 kg sample 2. how many ...

*October 22, 2012*

**world geography**

The answer is cultural

*October 17, 2012*

**world geo**

Physical is the answer

*October 17, 2012*

**Chemistry**

Just saw that I forgat to notice that the amount of potassium hydrogenphtalate was 5.12 grams. Also, it was enough with two readings within ± 0,01 cm3

*October 16, 2012*

**Chemistry**

We had a lab where the standard solution was potassium hdrogenphthalate. In this we added 3 drops of phenolphtalein indicator and then we ran sodium hydroxide into the solution. We did four different flasks and the final readings for these then were 26.00 cm3, 32.00 cm3, 26.10...

*October 16, 2012*

**Chemistry**

Using data from the following reactions and applying Hess's law, calculate the heat change for the slow reaction of zinc with water (answer must be in kJ/mol Zn): Zn(s) + 2 H2O(l) ----> Zn^2+(aq) + 2 OH-(aq) + H2(g) (ΔHrxn = ?) H+(aq) + OH-(aq) ----> H2O(l) (&#...

*October 15, 2012*

**Chemistry**

The complete combustion of 1.283g of cinnamaldeyde (C9H8O, one of the compounds in cinnamon) in a bomb calorimeter (Ccalorimeter=3.841 kJ/C) produced an increase in temperature of 130.32 C. Calculate the molar enthalpy of combustion of cinnamaldehydy (delta H comb) (in ...

*October 15, 2012*

**Chemistry**

So q/1.283 = 3841(130.32) I know you have to divide by the molar mass which I found to be 132.169 but Im not sure which number I divide it by.

*October 15, 2012*

**Chemistry**

The complete combustion of 1.283g of cinnamaldeyde (C9H8O, one of the compounds in cinnamon) in a bomb calorimeter (Ccalorimeter=3.841 kJ/C) produced an increase in temperature of 130.32 C. Calculate the molar enthalpy of combustion of cinnamaldehydy (delta H comb) (in ...

*October 15, 2012*

**Chemistry**

Phthalates used as plasticizers in rubber and plastic products are believed to act as hormone mimics in human. The value of deltaHcombustion for dimethylphthalate (C10H10O4) is 4685 kJ/mol. Assume 1.035 g of dimethylphthalate is combusted in a calorimeter whose heat capacity (...

*October 15, 2012*

**Chemistry**

Ok I got the answer!! Thank you!!

*October 15, 2012*

**Chemistry**

Ok, yeah I somehow read that as a label not as part of the equation, so 4685*(1.035/194.21)= 24.97 24.97*1000=24967.69 So then would the final equation be: 24967.69=7.293(Tfinal-20.142) Thank you by the way Im just really struggling with this.

*October 15, 2012*

**Chemistry**

How do you convert 4848.975 to J?

*October 15, 2012*

**Chemistry**

Phthalates used as plasticizers in rubber and plastic products are believed to act as hormone mimics in human. The value of deltaHcombustion for dimethylphthalate (C10H10O4) is 4685 kJ/mol. Assume 1.035 g of dimethylphthalate is combusted in a calorimeter whose heat capacity (...

*October 15, 2012*

**english**

I don't know what this one is. That's why i'm here for help!

*October 14, 2012*

**english**

Which one of the following statements is true for the base forms of verb? A. when the subject of a sentence is singular, add "-s" to the base form. B. Add "to" to the base form to create an adjective. C.Do not use a base form with plural subjects. D.Add &...

*October 14, 2012*

**english**

In this sentence, what is the antecedent of the pronoun it? A. her B. Carla C.house D.work?

*October 14, 2012*

**english**

which sentance contains an incorrect plural? A.The parties ended around midnight. B. If wishes were horses, beggars would ride. C.We spotted the foxs late in afternoon. D.I hate traffic delays.

*October 14, 2012*

**english**

A. river

*October 14, 2012*

**english**

We left King ranch on a december day in 1873. On the Santa Fe trail, we hit bad weather. The Red river was flooded and it took us four days to get the Cattle across. All in all, it was a hard trail drive, but we got our Longhorns to the railroad at Abilene. Which of the ...

*October 14, 2012*

**nouns pronouns and adjectives**

Which of the following shound be capitalized? a. river b railroad c drive d weather?

*October 14, 2012*

**Math**

Step 1: Find out what 10 to the 5th power is equal to. it = 100,000 Step 2: Multiply 100,000 by 10 Step 3: your answer = 1,000,000

*October 11, 2012*

**chemistry**

what is the chemical name and lewis structure of NO3 -2

*October 11, 2012*

**Polynomials**

A rock is thrown upward at a speed of 10 metres per second. The height of the rock above the ground is given by the formula h=10t-2.0t². Where h is the height in metres above the ground and t is the time in seconds. Then what is height after 5 second?

*October 11, 2012*

**chemistry**

how are the elements in a pair of isotopes the same? how do they differ? And also if you know anything about the atomic structure phrase apeman i could use some serious help right now i have a test tommoro and i cant remember all the material

*October 10, 2012*

**chemistry**

a new compound composed of just Hex-Nuts and bolts is formed.A 13.7 Kg sample of the new compound is separated into its component elements with the following result 3.84 kg. of hex-nuts and 9.90 kg of bolts. 1. How many hex-nuts are present in the 13.7 kg sample 2. how many ...

*October 10, 2012*

**bookkeeping**

Using your computer, you create a file for an existing costumer. When you're finished, you should a. overwrite the existing file by giving the new file the same name. b. use Save as to save the new file under a different name c. coordinate the old and new files b giving ...

*October 9, 2012*

**Physics**

In a head-on collision, a car stops in 0.14{\rm s} from a speed of 24{\rm m}/{\rm s} . The driver has a mass of 67{\rm kg} , and is, fortunately, tightly strapped into his seat. What force is applied to the driver by his seat belt during that fraction of a second?

*October 5, 2012*

**math-algebra**

one pump can empty a pool in 5 days, wheras a second pump can emtpy pool in 7 days. how long will it take the two pumps, working together, to empty the pool?

*October 5, 2012*

**chemistry**

Would you expect a chemical change to be always accompanied by a physical change?Pls. Explain

*October 5, 2012*

**chem**

Write the complete ionic equation for Cu(NO3(aq)+K2S(aq)and namd write the formula for the spectator ions in this reaction? This is what I got pls. check it: complete ionic equation: Cu^19aq)+K^1(aq)+S^-2(aq)=K^1(aq)+NO3^-1(aq)+Cu2S(s) net ionic equation: Cu(aq)+s^-2(aq)=Cu2S(...

*October 5, 2012*

**math**

Number 6 is actually ( -8, -10). I took the mother F***ing test and got that answer wrong because of you guys.

*October 3, 2012*

**Chemistry**

a student conducts and experiment by reacting 39.6g CuSO4 with an excess of MgS. The reaction yields 9.5599g CuS. What is the percentage yield? MgS+CuSO4=CuS+MgSO4

*October 3, 2012*

**Geometry**

Find the measure of each angle in a triangle with angles: x, (x-135), and 1/10 x

*September 30, 2012*

**chemistry**

A 27.00 mL sample of an unknown H3PO4 solution is titrated with a 0.110 M NaOH solution. The equivalence point is reached when 25.78 mL of NaOH solution is added. What is the concentration of the unknown H3PO4 solution? The neutralization reaction is: H3PO4(aq) + 3NaOH(aq) -&...

*September 27, 2012*

**science**

fill in the blank:the ____, the force acting on an object, the greater the acceleration of the object. It is 6 letters and the third letter is R

*September 26, 2012*

**math**

A student take in 2,300 calories and burns 2,500 calories. find the net change

*September 24, 2012*

**Algebra**

In 2007, Donald's stock portfolio decreased in value by 25%. In 2008, his stock portfolio decreased in value by another 40%. What percentage gain is required in 2009 for Donald's stock portfolio to return to the value it had in the beginning of 2007? (Round to nearest ...

*September 24, 2012*

**english**

what is the starting cause that made oddyseous go on the journey . please help i really don't know

*September 18, 2012*

**Algebra**

Find the distance between the points and the midpoint of the line segment joining them (p,0) (q,0)

*September 17, 2012*

**Algebra**

In which quadrants are the sign of first and second coordinates different

*September 17, 2012*

**Algebra**

Find x such that point (x,9) is 10 units from (9,3)

*September 17, 2012*

**Geometry**

if EF=2x-10 FG=3x-9, and EG=21 find the value of x, EF, and FG

*September 16, 2012*

**Chemistry**

Okay, I think I got it! Thanks a bunch :)

*September 16, 2012*

**Chemistry**

I have this problem.... Hexane has a density of 0.659 g/ml. How many milliliters (mL) would a student need to pour in order to get 49.5 g of hexane? Am I to solve by using mass = density x volume? And if so, is the answer 32.62mL?

*September 16, 2012*

**i don't understand this math**

4 is A those of u who think its c are wrong

*September 12, 2012*

**Algebra 2**

2x-y+=-9 3x-8y=-7 using the substitution method.

*September 10, 2012*

**AP Physics**

The volume of liquid flowing per second is called the volume flow rate "Q" and has the dimensions of [L]^3/[T]. The flow rate of a liquid through a hypodermic needle during an injection can be estimated with the following equation. Q = pi * R^n (P2 - P1) / 8ηL ...

*September 8, 2012*

**math**

500 becuase it takes away a hundred mph with the aerodynamicness

*September 7, 2012*

**Theory to Practice**

it would be b because it is one of the biggest obsticles as a begginner

*September 7, 2012*

**mr sus**

it will show the teacher that you have fully grasped the entire concept of what has been taught to you.

*September 7, 2012*

**Economics**

what exactly ?

*September 7, 2012*

**Chem**

What is 1250.37986 with 3 significant figures?

*September 6, 2012*

**Physics**

(a) Find the capacitance of a parallel-plate capacitor made of two 5 cm×5 cm square plates separated by 1 mm. (b) If 50 V is applied to this capacitor, how much energy is stored?

*September 4, 2012*

**Physics**

Three positive particles of charges 1 μC, 2 μC, 3 μC, and 4 μC, are located at the corners of a square of side 1 cm. Calculate the potential in the center of the square, taking V = 0 at a great distance.

*September 4, 2012*

**Physics**

How much work does the electric field do in moving a 2 μC charge from a point with a potential of +20 V to a point with a potential of −20 V?

*September 4, 2012*

**physics help please!**

Never mind I figured it out the answer is 67.3614 if anyone needs help

*September 3, 2012*

**physics help please!**

A race car is one lap behind the lead race car when the lead car has 57 laps to go in a race. If the speed of the lead car is 66.2 m/s, what must be the average speed of the second car to catch the lead car just before the end of the race (i.e., right at the ﬁnish line...

*September 3, 2012*

**physics**

Tammy leaves the oﬃce, drives 43 km due north, then turns onto a second highway and continues in a direction of 30◦ north of east for 80 km. What is her total displacement from the office? and At what angle is her displacement? (Consider east to be 0◦ and ...

*September 3, 2012*

**Math/Chemistry PLS HELP**

Find the absolute and percent relative uncertainty and express each answer with a reasonable amount of significant figures. 9.2(+ or -0.7)*(0.0054(+-0.3)+0.0056(+-0.7) The Algebraic answer: 0.1012 Absolute error? Relative error %?

*August 30, 2012*

**Health**

The answer is A. Added sugars are sugars and syrups that are added to foods or beverages when they are processed or prepared. This does not include naturally occurring sugars such as those in milk and fruits.

*August 30, 2012*

**Chemistry 314**

Five mineral samples of equal mass of calcite, CaCO3 (MM 100.085) , had a total mass of 12.4 ± 0.1 g. What is the average mass of calcium in each sample? (Assume that the relative uncertainties in atomic mass are small compared the uncertainty of the total mass.) (Input...

*August 30, 2012*

**chemistry**

A volume of 29.62 ± 0.05 mL of HNO3 solution was required for complete reaction with 0.8896 ± 0.0008 g of Na2CO3, (FM 105.988 ± 0.001). Find the molarity of the HNO3 and its absolute uncertainty. I have the molarity of HNO3 = 0.5667

*August 30, 2012*

**Chemistry**

A volume of 29.62 ± 0.05 mL of HNO3 solution was required for complete reaction with 0.8896 ± 0.0008 g of Na2CO3, (FM 105.988 ± 0.001). Find the molarity of the HNO3 and its absolute uncertainty. I have the molarity of HNO3 = 0.5667

*August 29, 2012*

**Chemistry**

Five mineral samples of equal mass of calcite, CaCO3 (MM 100.085) , had a total mass of 12.4 ± 0.1 g. What is the average mass of calcium in each sample? (Assume that the relative uncertainties in atomic mass are small compared the uncertainty of the total mass.) (Input...

*August 29, 2012*

**calculus 1**

THANK YOU!!!!!

*August 27, 2012*

**calculus 1**

If you can program a calculator or computer, estimate the length of the curve f(x) on the given interval using largest n's. f(x)=56cos(x), for x is greater than/equal to 0 and x is smaller than/equal to pi/2.

*August 27, 2012*

**Chemistry 314**

What NaCl concentration results when 254 mL of an 0.880 M NaCl solution is mixed with 412 mL of a 0.450 M NaCl solution?

*August 26, 2012*

**Chemistry**

I figured it out thanks to related questions.

*August 26, 2012*