Saturday

July 30, 2016
Total # Posts: 913

**Chemistry 1**

How many grams of a stock solution that is 92.5 percent H2SO4 by mass would be needed to make 250 grams of a 35.0 percent by mass solution? Can you please teach me how to do this? I get the other stoichiometry stuff, but this one tripped me up because I don't know how to ...
*February 1, 2011*

**chemistry**

A 0.100 mol sample of H2S is placed in a 10.0 L reaction vessel and heated to 1132°C. At equilibrium, 0.0285 mol H2 is present. Calculate the value of Kc for the reaction below at 1132°C. 2 H2S(g) 2 H2(g) + S2(g)
*January 31, 2011*

**Calculus**

A particle moves at varying velocity along a line and s=f(t) represents the particle's distance from a point as a function of time, t. Sketch a possible graph for f if the average velocity of the particle between t=2 and t=6 is the same as the instantaneous velocity at t=5...
*January 29, 2011*

**Chem**

What would be the resulting molarity of a solution made by dissolving 21.9 grams of KCl in enough water to make an 869-milliliter solution?
*January 27, 2011*

**Calc**

lim as x --> infinity of (x^2-16)/(x-4) is 8 By graphing, find an interval for near zero such that the difference between your conjectured limit and the value of the function is less than 0.01. In other words, find a window of height 0.02 such that the graph exits the sides...
*January 25, 2011*

**physics**

Can you help me with this one also? I know how to do it with 3 vectors but I can't seem to draw it with 4 vectors. The magnitudes of the four displacement vectors shown in the drawing are A=16.0 m, B=11.0 m, C=12.0 m, and D=26.0 m. Determine the (1) magnitude and (2) ...
*January 23, 2011*

**need help **

i'm in the 4th grade i need a socialstudy project to do rightnow i cant seam to think of anything can you help me please and thankyou
*January 23, 2011*

**physics**

A person is standing at the edge of the water and looking out at the ocean (see the drawing). The height of the person’s eyes above the water is h=1.6 m, and the radius of the earth is R=6.38x10^6 m (use as a precise value). (1) How far is it to the horizon (in meters, ...
*January 23, 2011*

**calculus**

Use a graph to estimate the limit: lim θ->0 (sin(5θ)/θ) Note: θ is measured in radians. All angles will be in radians in this class unless otherwise specified.
*January 22, 2011*

**Calculus**

A 0.3 ml dose of a drug is injected into a patient steadily for 0.35 seconds. At the end of this time, the quantity, Q, of the drug in the body starts to decay exponentially at a continuous rate of 0.4 percent per second. Using formulas, express Q as a continuous function of ...
*January 20, 2011*

**Calculus**

Consider the function f(x) = 5x^3 +5x^2 + 7, and let c be a number in the interval [0.1] . For what values of k is there a c in this interval such that f(c)=k? ______≤k≤______
*January 20, 2011*

**Physics**

9.6x10^-19
*January 19, 2011*

**Calculus**

According to Car and Driver, an Alfa Romeo going 70 mph requires 177 feet to stop. Assuming that the stopping distance is proportional to the square of the velocity, find the stopping distance required by an Alfa Romeo going at 55 mph and at 115 mph.
*January 19, 2011*

**Math**

What is the value of x? A isosceles triangle: bottom - x+3 one side - 2x+5 other side - 3x+2
*January 17, 2011*

**calculus**

On the graph of f(x)=6sin(8πx), points P and Q are at consecutive lowest and highest points with P occuring before Q. Find the slope of the line which passes through P and Q.
*January 15, 2011*

**Calculus**

In the year 2005, a picture supposedly painted by a famous artist some time after 1815 but before 1865 contains 96.5 percent of its carbon-14 (half-life 5730 years). From this information, could this picture have been painted by this artist? Approximately how old is the ...
*January 13, 2011*

**Calculus**

The half-life of radioactive strontium-90 is approximately 31 years. In 1960, radioactive strontium-90 was released into the atmosphere during testing of nuclear weapons, and was absorbed into people's bones. How many years does it take until only 11 percent of the ...
*January 13, 2011*

**math**

so you will be using the formula y=mx+b to plug the given values into. m=slope which is 8, here b=y-intercept which is 5 so your slope-intercept equation is... y=8x+5
*January 13, 2011*

**Physics**

Density of marble is 2.7 x 10^3 kg/m^3... Idk if that helps?
*January 4, 2011*

**Physics**

A ball of mass 0.640 kg moving east (+x direction) with a speed of 3.00 m/s collides head-on with a 0.740 kg ball at rest. If the collision is perfectly elastic, what will be the speed and direction of each ball after the collision?
*December 19, 2010*

**Maths**

I need help in this subject not to answer a question that I dont even understand.So somebody needs to help me understond this question.Not give me another question to answer.ok.ok
*December 18, 2010*

**math**

volume of a triangular prism
*December 16, 2010*

**Chemistry URGENT**

If a student starts with 615g of Co(NO3)2 and obtains a 57.3% yield of CoS, what mass of CoS is isolated? Co(NO3)2 + K2S ---> CoS + 2KNO
*December 16, 2010*

**Chemistry**

If a student starts with 615g of Co(NO3)2 and obtains a 57.3% yield of CoS, what mass of CoS is isolated? Co(NO3)2 + K2S ---> CoS + 2KNO3
*December 16, 2010*

**geography**

Affordable housing and improved transportation allowed people to begin to move away from central cities to the suburbs Think: When did affordable housing and highways come about? The industrial revolution gave rise to urbanization Think: When was the first occurrence of ...
*December 15, 2010*

**Chemistry**

I thought it was going to be easier than that.. honestly.. I'm better with math like calculus and formulas.
*December 15, 2010*

**Chemistry**

The four quantum numbers for the last electron placed in the orbitals of a certain element are: n=3 l=2 m of l=0 and m of s=-1/2. What is the element?
*December 15, 2010*

**General Chemistry**

Well I'm studying for my final and he gave us an answer key and with a spin down it says that the answer is nickel.. SOO I'm trying to make sense of it but I understand what n is what l is but how do you figure out what the elements are from ml? And all of that put ...
*December 14, 2010*

**General Chemistry**

The four quantum numbers for the last electron placed in the orbitals of a certain element are: n=3 l=2 m of l=0 and m of s=-1/2. What is the element? I need help with this part of chemistry I have NEVER understood this ever. I know how to do the configurations but not this. I...
*December 14, 2010*

**hum 176**

Write a thesis sentence about a movie stating how and why it is more than just a piece of entertainment. The thesis must include why it is a legitimate form of popular culture. Keep in mind factors such as influence and controversy.
*December 13, 2010*

**Physics**

The front 1.20 m of a 1550 kg car is designed as a "crumple zone" that collapses to absorb the shock of a collision. (a) If a car traveling 26.0 m/s stops uniformly in 1.20 m, how long does the collision last? cannot_evaluate s (b) What is the magnitude of the ...
*December 9, 2010*

**history**

Thank You!
*December 9, 2010*

**history**

Why did the Supreme Court rule that segregation was constitutional?
*December 9, 2010*

**Chemistry**

a 2.4375 g sample containing a mixture of KClO3 + NaCl is heated and undergoes a mass loss of 0.6191g. What percent of KClO3 is in the mixture?
*December 9, 2010*

**Chemistry**

a 2.4375 g sample containing a mixture of KClO3 + NaCl is heated and undergoes a mass loss of 0.6191g. What percent of KClO3 is in the mixture?
*December 9, 2010*

**Chemistry**

a 2.4375 g sample containing a mixture of KClO3 + NaCl is heated and undergoes a mass loss of 0.6191g. What percent of KClO3 is in the mixture?
*December 9, 2010*

**Chemistry**

a 2.4375 g sample containing a mixture of KClO3 + NaCl is heated and undergoes a mass loss of 0.6191g. What percent of KClO3 is in the mixture?
*December 9, 2010*

**Chemistry**

A 2.4375 g sample containing a mixture of KClO3 and NaCl is heated and under goes a mass loss of 0.6191 g. What is the percent of KClO3?
*December 9, 2010*

**Chemistry**

I ended up getting 42.718333 not rounded to sig figs but does the excess of hydrochloric acid have anything to do with the answer and what about the STP?
*December 8, 2010*

**Chemistry**

If you have Hydrochloric acid, how many grams of aluminum must you use to produce 57.0 L of hydrogen at STP? 2Al(s)+6HCl(aq) --> 3H2(g)+2AlCl3(aq)
*December 8, 2010*

**Chemistry**

The specific heat capacity of Lead is 0.127J/degrees C*g. What is the molar heat capacity of Lead? What is the heat capacity of a lead cylinder that has a mass of 235000g?
*December 8, 2010*

**chemistry**

specific heat of water there isnt one?
*December 8, 2010*

**chemistry**

How much heat energy in KJ is evolved by a reaction in a calorimeter in which the temperature of the calorimeter and water increases from 20.91 degrees C to 26.45 degrees C? The bomb has a heat capacity of 469 J/degrees . The Calorimeter contaains 792 grams of water.
*December 8, 2010*

**Chemistry**

Calculate the weight percent of water in NiSO4 6H2O, how to calculate it?
*December 8, 2010*

**alg 2**

to find 'x' you add 243 to both sides so: 3x^2=243 divide both sides by 3 3x^2/3 = 243/3 x^2 = 81 then take the square root of both sides so x=9 hope that helps, be sure to plug your numbers back in to check it take 9 and plug it in for x :: 3(9)^2-243 3(81)-243 243-...
*December 8, 2010*

**Chemistry**

Calculate the weight percent of water in NiSO4 6H2O, how to calculate it?
*December 8, 2010*

**Chemistry**

Calculate the weight percent of water in NiSO4 6H2O, how to calculate it?
*December 8, 2010*

**college Chemistry**

B. because it jumps straight from 1s2 to 2p1 it has to go :: 1s2 2s2 then 2p1
*December 6, 2010*

**advice**

could you mark each verb used in bold. identify the specific tense used in parentheses. I have seen many examples of different saving plans. I planned on using these strategies in my personal life.
*December 5, 2010*

**physics**

but what if it asks how long it will take to fall?
*December 4, 2010*

**physics**

OH!! so thats where i went wrong. thanks again! ^w^
*December 4, 2010*

**physics**

so its 2*9.81*155?
*December 4, 2010*

**physics**

The single cable supporting an unoccupied elevator breaks when the elevator is at rest at the top of a 155 m high building. With what speed does the elevator hit the ground?
*December 4, 2010*

**physics**

At the instant a traffic light turns green, a car starts moving with a constant acceleration a of 4.00 m/s2. At the same instant a truck, traveling with a constant speed of 10.09 m/s, overtakes and passes the car. How far beyond the traffic light will the car overtake the truck?
*December 4, 2010*

**physics**

thank u so much!! ^w^
*December 4, 2010*

**physics**

so how would i go about finding acceleration?
*December 4, 2010*

**physics**

The airplane can take off when its airspeed (speed of the air flowing over the wing) is equal to 65 knots. What is the length of runway required for the plane to take off if there is a 21 knots head wind? The runway at the Tallahassee Regional Airport has a length of 8000 ft.
*December 4, 2010*

**Biology**

I need help making a concept map. I have to put the following words into one and i dont know where to start. Gene DNA Chromosome Mutations Protiens Central Dogma Signal Transduction Nucleus mRNA tRNA rRNA Ribosomes Autosomes Sex Chromosomes Recessive Translation Transcription ...
*December 3, 2010*

**W.H.Atwell**

Does 2Na 2H2O 2NaOH H2 shows that the total mass during a chemical reaction stays the same?
*December 1, 2010*

**12th grade English**

ok thank u anyway
*November 30, 2010*

**12th grade English**

o an thanks
*November 30, 2010*

**12th grade English**

srry its catcher in the rye
*November 30, 2010*

**12th grade English**

I need help i have to have a literary term for ch. 1,2,3,5,12,13,14,16,and 26 im having trouble figuring out how to do that so can somone help me please
*November 30, 2010*

**Chemistry**

Calculate the percent of carbon, hydrogen, nitrogen, and oxygen in this widely used pesticide, Sevin. The molecular formula is C12 H11 O2 N.
*November 23, 2010*

**Chemistry**

Calculate the percent of carbon, hydrogen, nitrogen, and oxygen in this widely used pesticide, Sevin. The molecular formula is C12 H11 O2 N.
*November 23, 2010*

**chemistry**

combustion of 0.356g of an unknown metal sample in oxygen gives 0.452g of an oxide in the form of mO2, Identify the unknown metal?
*November 23, 2010*

**Chemistry**

A gas has a volume of 4.00 at 0. What final temperature in degrees Celsius is needed to cause the volume of the gas to change to the following, if (number of moles of gas) and are not changed? 290 L
*November 23, 2010*

**chemistry**

how do you figure that out?
*November 23, 2010*

**chemistry**

What mass of Zn can be dissolved by 558 mL of 3.01M HCl?
*November 23, 2010*

**ela**

if you unscramblethe letters SATLEIVER what word do u get and it has to do with thanksgiving
*November 22, 2010*

**algebra**

The following problem has a total of six solutions each. (X^2-5x+5)^x^2-9x+2=1. Its extra credit
*November 19, 2010*

**Physics**

Find the heat necessary to change 2.5kg of water (ice) at -2 degrees C to steam at 105 degrees C. specific heat ice= 2060 specific heat water= 4180 specific heat steam= 2020 heat of fusion= 3.34X10^5 heat of vaporization= 2.26X10^6
*November 18, 2010*

**Physics**

How much heat must be added to 3kg of liquid water at 25 degrees C to change it into steam at 120 degrees C?
*November 18, 2010*

**physics**

a banana with a temperature of 17 degrees C (specific heat of banana= 3520j/kgK) and a a mass of 250g is placed in a bowl of milk with a temperature of 8 degrees C and a mass of 350g (specific heat of milk= 4200 J/kgK). no heat is lost to the bowl or the air as the banana and ...
*November 18, 2010*

**Physics**

lead melts at 328 degrees C. lead has a heat of fusion of 2.04X10^4 J/kg and a specific heat of 130 J/kgK. how much heat must be removed from 0.50 kg of molten lead (liquid) at 328 degrees C to make it all a solid chunk at 300 degrees C?
*November 18, 2010*

**5th grade science**

blank a type of material that tries to prenent the flow of thermal energy.
*November 15, 2010*

**Social Studies**

to.................much.....................................for..............................................................brain........................................................................................................AHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH...
*November 10, 2010*

**math-- please help **

A minor league baseball pitcher is hired for $700 per month plus $100 per game won. Write an equation to express his monthly earnings (e) in terms of games won (x).
*November 5, 2010*

**math --slope and y intercept**

A funiture refinishing outlet pays its employlees $40 per day plus $10 per unit refinished. Write an equation to express an employees daily wage(w) in terms of units finished(x)
*November 5, 2010*

**Chemistry**

A solution contains an unknown mass of dissolved silver ions. When potassium chloride is added to the solution, a white precipitate forms. The precipitate is filtered and dried and then found to have a mass of 245 mg. What mass of silver was in the original solution? (Assume ...
*November 4, 2010*

**STATISTICS PLEASE HELP!!!!!**

are you a chocolate "purist", or do you like other ingredients in your chocolate? american demographics reports that almost 75% of consumers like traditional ingredients such as nuts or caramel in their chocolate. they are less enthusiastic about the taste of mint or...
*November 3, 2010*

**linear equations -math **

Find the equation of a line through the points (-2,3)and (-4,5)
*November 3, 2010*

**math **

Find the equation of a line through the points (-2,3)and (-4,5)
*November 2, 2010*

**math**

FInd the equation of a line through the point (-2,5) with a slope of -2
*November 2, 2010*

**9th grade**

WHAT IS THE SQUARE ROOT OF 192?
*November 1, 2010*

**lee senior**

what is -2x+y=-4
*November 1, 2010*

**Maths**

60 degree angle
*October 31, 2010*

**math**

people are attending a sold out concert there. thirty minutes before it starts 15,000 people are there.how many people have not arrived yrt?
*October 28, 2010*

**WESTERN CIV!**

can you give me a summary of the Iliad by Homer?
*October 20, 2010*

**Chemistry**

A 26.7 g sample of ethylene glycol, a car radiator coolant, loses 668 J of heat. What was the initial temperature of ethylene glycol if the final temperature is 32.5°C (c of ethylene glycol = 2.42 J/gK)?
*October 20, 2010*

**Chemistry**

One piece of copper jewelry at 101°C has exactly twice the mass of another piece, which is at 36.0°C. Both pieces are placed inside a calorimeter whose heat capacity is negligible. What is the final temperature inside the calorimeter (c of copper = 0.387 J/gK)?
*October 19, 2010*

**Chemistry**

A 26.7 g sample of ethylene glycol, a car radiator coolant, loses 668 J of heat. What was the initial temperature of ethylene glycol if the final temperature is 32.5°C (c of ethylene glycol = 2.42 J/gK)?
*October 19, 2010*

**Trig**

A force of 323 newtons makes an angle of 54 degrees and 20 minutes with a second force. The resultant of the two forces makes an angle of 39 degrees forty minutes with the first force. Find the magnitude of the second force. I have the answer, 814.3022, but I need to know how ...
*October 19, 2010*

**HELP! INTRO TO ECO**

Why do supply curves slope upward from left to right? Why don't we sometimes draw them sloping downward from left to right? Under what conditions would it be sensible to draw a supply curve that is horizontal(perfectly elastic)? Under what conditions would it be sensible ...
*October 12, 2010*

**Intro to Eco Help**

supply curves slop upward to the right because.. higher prices attract resources from other uses?
*October 11, 2010*

**ECONOMICS HELP**

a draft system, whether professional sports or the military, enable those who are hiring to A.avoid paying a living wage B.produce what they produce at a lower cost C.educe the cost of labor D.transfer part of the cost of labor to someone other than themselves isnt B the ...
*October 11, 2010*

**ECONOMICS HELP**

a draft system, whether professional sports or the military, enable those who are hiring to A.avoid paying a living wage B.produce what they produce at a lower cost C.educe the cost of labor D.transfer part of the cost of labor to someone other than themselves isnt B the ...
*October 11, 2010*

**intro to economics **

a draft system, whether professional sports or the military, enable those who are hiring to A.avoid paying a living wage B.produce what they produce at a lower cost C.educe the cost of labor D.transfer part of the cost of labor to someone other than themselves isnt B the ...
*October 11, 2010*

**Intro to ECONOMICS**

the basic reason suburban stores are more likely than downtown stores to provide free parking for their customers is that.. the cost of using land is higher in the downtown area?
*October 11, 2010*