Thursday

September 29, 2016
Total # Posts: 3,236

**chem- plz check my work**

2. Given the following equation, C2H5OH(l) + 3 O2(g)---> 2 CO2(g) + 3 H2O(l) How many liter of CO2 are expected in the combustion of 12.0 grams of ethanol? My work: 12.0g C2H5OH X 1 mol C2H5OH/46.08g C2H5OH X 2 mol CO2/1 molC2H5OH X 22.4L CO2/1 mol CO2 = 11.7 L CO2 all i ...

*December 8, 2010*

**chemisty**

when looking at a chemical equation what are the evidences that a chemical reaction has occured. Or what is the evidence that it has not occured thanks:):) <3

*December 8, 2010*

**Physics**

What is the volume of 3.25 moles of a gas at a temperature of 115 K and a pressure of 275 kPa?

*December 8, 2010*

**Physics**

A pendulum is constructed of a 6.7 gram mass suspended on a 55cm thread. The mass is displaced vertically 55 cm to a point exactly horizontal from the top of the thread and released. The mass swings down and is cut directly above the mass when the mass is 120 cm above the ...

*December 7, 2010*

**CHOIR**

can you find the music online? Why not just ask her for another copy when you get to school tomorrow and tell her what happened

*December 7, 2010*

**english**

I need two examples where in the book Huckleberry finn. Huck doesn't believe in himself or he is having self doubt. does anyone know an example or two where this happens in the book? thanks

*December 7, 2010*

**chem**

how would you find the answer? A carbon nucleus has six protons and six neutrons. How many electrons would it take to equal the mass of a carbon nucleus?

*December 6, 2010*

**chem**

can you explain? For each of the reactions shown, calculate how many grams of the product form when 16.8 g of the reactant in bold completely reacts. Assume that there is more than enough of the other reactant. 4 Cr(s) + 3 O2(g) 2 Cr2O3(s) thanks

*December 6, 2010*

**huckleberry finn**

in the book huckleberry finn manys words are used that mean something like "to beat someone" for example to lick. i need to find 8 more of words that are used to mean "to beat" if you know any and the page number/chapter it is used in the book that would be...

*December 5, 2010*

**Chemistry**

because you take the ratio and just use them as subscripts for its corresponding element. So if carbon came out to 2 and hydrogen came out to 6, then it would simply be C2H6.

*December 4, 2010*

**Chemistry**

It would be C2H6

*December 4, 2010*

**Calculus **

Find the unique solution to the differential equation y"?1y'?6y=?24(t^2)+10t+41 satisfying the initial conditions y(0)=?6 and y'(0)=?26

*December 3, 2010*

**Calculus **

(1 pt) Find the unique solution to the differential equation y"?5y'+6y=?312sin(2t) satisfying the initial conditions y(0)=?31 and y'(0)=?18

*December 3, 2010*

**Geometry**

You do 1/2 base times height, so 1/2(14cm)(18cm)=126cm. Dont forget units! Your welcome:)

*December 1, 2010*

**Math fractions**

You must make the denominators the same by multiplying the numerator and the denominator of 1/2 by four to get 4/8. Your welcome:)

*December 1, 2010*

**huckleberry finn**

also the word valley on page 174( at least in my book) its in the context that reads "the king said the cubby would do for his valley- meaning me"

*December 1, 2010*

**huckleberry finn**

what is the definition of dauphin this huckleberry finn? I searched on the internet but there were so many i didnt know which one was used in the book

*December 1, 2010*

**math**

Use a table of values to graph the equation. solve for y x= -1,0,1 y= y=2/3x+6

*November 30, 2010*

**chem**

I got it:) it was just not a precipitate:) Thankyou sooooo much:)

*November 30, 2010*

**chem**

could it also be an acid-base?

*November 30, 2010*

**chem**

or acid- base? because i did gas evolution oxidation-reduction precipitation single-displacement but got it wrong so I am thinking either one of those has to be taken out and/or acid-base added

*November 30, 2010*

**chem**

its not also a precipitation os single-displacement??

*November 30, 2010*

**chem**

Ca(s) + 2 H2O(l) Ca(OH)2(aq) + H2(g) acid-base double-displacement gas evolution oxidation-reduction precipitation single-displacement synthesis whichs one(s) is it?? thanks

*November 30, 2010*

**chem**

oops sorry

*November 30, 2010*

**chem**

thanks you so much. Also if i may ask im having trouble on another type of problem balancing this equation: C5H12O(l) + O2(g) --> H2O(g) + find the compound here I am able to balance it but i need to find the last compound i though it would be: C5H10O2 because i took out 2 ...

*November 30, 2010*

**chem**

thanks. so would it be double displacement and acid-base?

*November 30, 2010*

**chem**

Classify each of the following reactions in as many ways as possible. (Select all that apply.) CuO + 2 HCl --> CuCl2 + H2O you can select: -acid-base(unsure because there is an acid but im not sure if theres a base) -double-displacement -gas evolutionx -oxidation-reduction ...

*November 30, 2010*

**Geometry **

SORRY I FORGOT SOME QUESTI IN MY LAST POST!!! The lengths of two sides of a triangle are given. Describe the possible lenths for the third side. 19.) 5,11 20.) 12,12 21.) 25,10 22.) 6,8 25.) A student draws a triangle with a perimeter 36 cm. The students says that the longest ...

*November 29, 2010*

**Geometry**

THANK YOU SO MUCH!

*November 29, 2010*

**Geometry**

Can a triangle have sides with the given lengths? Explain. 15) 8cm, 7cm, 9cm 16) 7ft, 13ft, 6ft 17) 20in, 18in, 16in 18) 3m, 11m, 7m

*November 29, 2010*

**chem**

oh sorry i miss read what you put. thanks

*November 29, 2010*

**chem**

oh theres an arrown after Br2

*November 29, 2010*

**chem**

so is it just synthesis?

*November 29, 2010*

**chem**

I am having lots of trouble with these questions: Classify each of the following reactions in as many ways as possible. (Select all that apply.) a)2 Rb(s) + Br2(g) 2 RbBr(s) you can select: -acid-base -double-displacement -gas evolution -oxidation-reduction -precipitation -...

*November 29, 2010*

**Health**

what is the drug classification of inhalants?

*November 28, 2010*

**french, english**

oh thanks sooo much:)

*November 28, 2010*

**chem**

oh i got it:) thanks:)

*November 28, 2010*

**math**

48 is another one

*November 28, 2010*

**OMG**

The main teachers that are on this site that specialize in your subject just might not be on around this time. be patient and give it time and im sure someone will be able to help :)

*November 28, 2010*

**chem**

balance the equation:(i can balance the equation but the problem i have is finding the formula for the last part HC2H3O2(aq) + Ca(OH)2(aq) -> H2O(l) + find the formula here the last part would be CaOC2H3O2? im a little confused. did the O fromt he H2O come from (OH)2?

*November 28, 2010*

**chem**

thanks so for this equation: HC2H3O2(aq) + Ca(OH)2(aq) -> H2O(l) + find the formula here the last part would be CaOC2H3O2? im a little confused. did the O fromt he H2O come from (OH)2?

*November 27, 2010*

**chem**

balance the formula Cu(OH)2(s) + HNO3(aq) -> H2O(l) + fine the formula here(aq) i did the H20 but i don't know the other formula i thought it was CuNO3 but thats wrong and idk what to do with the extra O

*November 27, 2010*

**math brain teaser**

more it it thani what does that mean??? also: EVELATOR and: DENTURES E F

*November 24, 2010*

**geometry**

use the a^2 + b^2 = c^2 c being the length of the hypotenuse

*November 23, 2010*

**chem**

I need major help im not understanding this at all: Complete and balance each of the following equations for acid-base reactions. (Type your answer using the format CO2 for CO2 and Al(OH)3 for Al(OH)3. Use the lowest possible coefficients.) HBr(aq) + LiOH(aq) -> find this ...

*November 23, 2010*

**history**

I would say D also :)

*November 23, 2010*

**chem**

thanks sooo much!!

*November 23, 2010*

**chem**

this is what it says: For the soluble compounds, write the ions present in solution. this is the soluble compound: Na3PO4 then it has 2 boxes one called cations and one called anions

*November 23, 2010*

**chem**

it says those answers are wrong

*November 23, 2010*

**chem**

I put Na+ as the cation and it counted it wrong. also. are you saying PO4- is the anion? cause i got it wrong. and what do the noble gases have to do with the ions. sorry im asking many questions

*November 23, 2010*

**chem**

can you explain more? i put the cation was Na3+ and the anion was PO4-. but it said it was wrong. what am i doing wrong?

*November 23, 2010*

**chem**

how do i know what the ions present are of this formula: Na3PO4 what are the anions and what are the cations? how do you know

*November 23, 2010*

**Math**

Thank you!!!

*November 22, 2010*

**Math**

An object is heated to 90 degrees Celcius and is then allowed to cool in a room whose air temperature is 25 degrees celcius. If the temperature of the object is 75 degrees celcius after 10 minutes, when will its temperature be 50 degrees celcius?

*November 22, 2010*

**chem**

Balance the skeletal equation for the synthesis of urea. (Enter 0 for any empty boxes. Use the lowest possible coefficients.) _NH3 + _CO2 ¨ _CO(NH2)2 + _H2O in the _ goes a number

*November 22, 2010*

**maths**

well it has to end in 0 to be divisible by 10. I got:360 because 8 and 9 both go in evenly

*November 22, 2010*

**maths**

i am divisible by 8 and9.i am a three digit multiple of 10. i am between 200 and 700.

*November 22, 2010*

**chem**

nevermind i got it

*November 22, 2010*

**chem**

Aluminum hydroxide and sulfuric acid neutralize to make water and aluminum sulfate. the first step i have done: Al(OH)3 + H2SO4 -> H2O + Al2(SO4)3 i find this one confusing XD

*November 22, 2010*

**chem repost**

I got most of it but there is one coefficient its counting wrong. i posted my problem on the previous post. would you like me to post it here also?

*November 21, 2010*

**chem repost**

oh. sorry i didn't see my other post was answered thanks

*November 21, 2010*

**chem repost**

write a balanced equation for:Gaseous carbon dioxide and liquid water react to produce aqueous glucose (C6H12O6) and oxygen gas. I try but everytime i change the coefficient it makes the other elements unbalanced. the starting formula i got was: CO2(g) + H2O(l) -> C6H12O6(...

*November 21, 2010*

**Math**

An object is heated to 90 degrees Celcius and is then allowed to cool in a room whose air temperature is 25 degrees celcius. If the temperature of the object is 75 degrees celcius after 10 minutes, when will its temperature be 50 degrees celcius? I have no idea how to do this...

*November 21, 2010*

**chem**

thanks! i didnt see the 2 after the H

*November 21, 2010*

**chem**

so what i have so far is: 6-CO2(g) + 12- H2O(l) -> 1-C6H12O6(aq) + 6- O2(g) it said all the coefficients were correct except the 12 in front of the H20 how is that wrong?

*November 21, 2010*

**chem**

write a balanced equation for:Gaseous carbon dioxide and liquid water react to produce aqueous glucose (C6H12O6) and oxygen gas. I try but everytime i change the coefficient it makes the other elements unbalanced. the starting formula i got was: CO2(g) + H2O(l) -> C6H12O6(...

*November 21, 2010*

**Math**

An object is heated to 90 degrees Celcius and is then allowed to cool in a room whose air temperature is 25 degrees celcius. If the temperature of the object is 75 degrees celcius after 10 minutes, when will its temperature be 50 degrees celcius? I have no idea how to do this...

*November 21, 2010*

**Math**

Thank You

*November 20, 2010*

**Math**

A bone is found to have 45% of the original amount of carbon 14. If the half life of carbon is 5600 years, how old is the bone. Would I use the formula N=No e^kt?

*November 20, 2010*

**Math**

Thank You

*November 20, 2010*

**Math**

A colony of bacteria increases according to the law of unihabited growth. a) If the number of bacteria doubles in 5 hours, find the function that gives the number of cells in the culture. I have the answer to this one. It is N=No e ln2/5 (t) b) If there are 10,000 cells ...

*November 20, 2010*

**chem**

is An antacid neutralizes stomach acid. a chemical reaction?

*November 20, 2010*

**7th grade**

unless you just look to the next chapter of your text book if its something like math and you read that and try to understand it.

*November 20, 2010*

**Calculus**

Find the particular solution of the differential equation y'=(5x+21y)/7x satisfying the initial condition y(1)=5.

*November 18, 2010*

**Calculus**

1)Find the particular solution of the differential equation xy'+3y=80xlnx (x>0) satisfying the initial condition y(1)=4 2)Find the particular solution of the differential equation y'−1y=−5x+3 satisfying the initial condition y(0)=3.

*November 18, 2010*

**precal**

Find the value of sec theta for angle theta in standard position if the point at (–2, –4) lies on its terminal side. If 0° lessthanorequalto x lessthanorequalto 360°, solve the equation sec x = –2. The terminal side of an angle theta in standard position...

*November 17, 2010*

**Ethics**

What is speciesism? I have already defined it on google but could simply the definition?

*November 16, 2010*

**chem**

The rock in a lead ore deposit contains 84% PbS by mass. How many kilograms of the rock must be processed to obtain 1.1 kg of Pb? i need to know what the conversion factors look like and how u did it

*November 16, 2010*

**physics**

5 m/s

*November 16, 2010*

**social studies**

how did the Nile and the surrounding area help protect Egypt?

*November 16, 2010*

**chem**

thanks!!!

*November 15, 2010*

**chem**

i had posted this question about a week ago and had gotten help from bobpursley(thank you so much btw) but i was showed how to do it using an equationa and now when im studying for the test i realize i need to be able to make a conversion factor to solve it. so heres the ...

*November 15, 2010*

**english**

thats a little helpful but im kinda looking more for why the slang was used. was it easier for them?faster? and how did it all start up? did the soldiers just start using the words and everyone learned them? things like that

*November 15, 2010*

**english**

For english i need to write a paper of the the slang words used during the civil war. I already have many examples but i cant seem to find history or facts about it. am information that you know would be helpful like origin, history,who came up with the words etc. thanks so ...

*November 15, 2010*

**physics**

What length pendulum will produce a period of 1.0s?

*November 14, 2010*

**physics**

you measure the period of a 2.0m pendulum and find it is 2.8s. what is the value of g at your location?

*November 14, 2010*

**math **

5^3= 5x5x5= 125 5^7=5x5x5x5x5x5x5= 78125

*November 14, 2010*

**chem**

Citric acid, the compound responsible for the sour taste of lemons, has the following elemental composition: C, 37.51%; H, 4.20%; O, 58.29%. Calculate the empirical formula of citric acid. (Type your answer using the format CO2 for CO2.) thanks

*November 14, 2010*

**physics**

If the coefficient of kinetic friction between a 37 kg crate and the floor is 0.31, what horizontal force is required to move the crate at a steady speed across the floor? What horizontal force is required if µk is zero?

*November 14, 2010*

**physics**

A person jumps from the roof of a house 4.9 m high. When he strikes the ground below, he bends his knees so that his torso decelerates over an approximate distance of 0.70 m. The mass of his torso (excluding legs) is 46 kg. (a) Find his velocity just before his feet strike the...

*November 14, 2010*

**chem**

A 2.241 g sample of nickel reacts with oxygen to form 2.852 g of the metal oxide. Calculate the empirical formula of the oxide. 1)NiO Give the number of moles of each element to support you answer. moles of Ni 2) 1.339 mol moles of O 3)1.34 mol I know #1 is correct but 2 and 3...

*November 12, 2010*

**science**

suppose you had two samples of the same radioactive isotope. one sample had a mass of 25 grams. the other had a mass of 50 grams. would the same number of particles be ejected from each sample in the first hour? explain

*November 11, 2010*

**chem**

oh i see! thanks

*November 11, 2010*

**chem**

shouldn't it be less than the 4.7 g of silver plating??

*November 11, 2010*

**chem**

so the mass would be 6.24g?

*November 11, 2010*

**chem**

Silver chloride, often used in silver plating, contains 75.27% Ag. Calculate the mass of silver chloride in grams required to make 4.7 g of silver plating.

*November 11, 2010*

**chem**

i got the answer. thanks anyways!

*November 11, 2010*

**chem**

A 4.91 g sample of aluminum completely reacts with oxygen to form 6.85 g of aluminum oxide. Use this data to calculate the mass percent composition of aluminum in aluminum oxide. i got 61.2% first and it was wrong. then i got 53.0% and it was wrong

*November 11, 2010*

**Math**

I figured it out. -8=1/3x+x -8*3=1/3x*3+x -24=3x+x -24=4x -24/4+4x/4 -6=x -8=1/3*-6+-6 -8=-6/3-6 -8=-2-6 -8=-8

*November 10, 2010*

**Math**

-8=1/3x+x

*November 10, 2010*