# Posts by Hannah

Total # Posts: 3,348

**us history**

What was Scott Joplin most known for duirng the 1920's? please do not just give me a url to a site with his biography because i have already looked at many! I am trying to narrow my answer down to 3 sentences. thanks!

**5TH GRADE MATH**

the rule is subtract 8. I'm not sure if that's what you're asking or not but that's my answer! Hope it helped:D

**french**

I have a project where I have to make a video about the differences between arts in USA and in Alsace, France. Arts meaning painting, sculpture, music that kind of thing. I have been try to research but have not come up with much. I don't really know what to search and ...

**Animal Science**

I need a statistic of how many dogs and cats are currently in a foster home in the us. Does anyone know a website that has this credible statistic? thanks

**math**

how would i find the area of the parallelogram if the area of each right triangle region is 7 1/2 square inches

**Algebra (direct variation)**

the value of y varies directly with x, and y=-2 when x=-4 Find y when x=8 -2=k(-4)

**Math**

for the point deterime all six trigonometric ratios and the value of the principal angle and the related acute angle P( -3,0)

**math**

a store has a total of 108 full-time staff and part time staff. There are three times as many full-time staff as part time staff. How many of the staff are in each category?

**Chemistry(Please help)**

Nitrogen monoxide + Hydrogen --> nitrogen + water I need to balance this equation but I do not know how. NO + H --> N + H2O 2NO + 2H --> 2N Would this be correct? Thank you!!

**history**

what offically started and ended WWI? and what made the us enter the war?

**chemistry**

sulfur dioxide (g) + oxygen (g) sulfur trioxide (g) SO2 + O = SO3 Is this correct for the balanced equation?

**chemistry(Urgent Please help)**

A student is asked to standardize a solution of barium hydroxide. He weighs out 0.945 g potassium hydrogen phthalate (KHC8H4O4, treat this as a monoprotic acid). It requires 33.9 mL of barium hydroxide to reach the endpoint. A. What is the molarity of the barium hydroxide ...

**Chemistry**

A 8.71 g sample of an aqueous solution of hydroiodic acid contains an unknown amount of the acid. If 25.0 mL of 0.388 M barium hydroxide are required to neutralize the hydroiodic acid, what is the percent by weight of hydroiodic acid in the mixture? I understand how to solve ...

**speech**

I am doing a persuasive speech on why you should foster a dog or cat. but I am not sure what my three main points should be. do you guys have any idea?

**Chemistry**

I am doing similar homeowrk and I was wondering how you calculate the ph after the equivalence point?

**History**

diary + the poems he wrote

**History**

so was his main contribution when he fuoght with the french or the diary that he kept that showed what the war was like?

**History**

What was Alan Seeger do that made an impact during WWI?

**Chemistry**

For a lab experiment we have to draw the lewis structures of hydrides. 1) Carbon It asks for the formula of hydride. Total # of valence electrons and the lewis structure. Total electrons would be four. I am not sure what the formula would be or how to find that and and the ...

**Chemistry**

The compound butane, has two structures. They have the same molecular formula but different arrangements of bonds in their structures. As a result, they can have different chemical and physical properties. Draw the lewis structures of all the isomers of pentane, C5H12. I am ...

**geometry**

why do elephants have pointy tails

**Math**

Your friend states that your mortgage is "an annuity where you are the bank."What does she mean?

**Chemistry**

Is the structure for chlorous acid H O Cl O or H Cl O ? O I was thinking that both could be correct but I am not 100% sure.

**Chemistry**

Is the structure for chlorous acid H O Cl O or H Cl O ? O I was thinking that both could be correct but I am not 100% sure.

**physics**

Two dogs pull on a toy. One pulls with a force of 10 N, the other with a force of 15 N. (a) In what relative directions can the dogs act to give the toy the smallest acceleration?

**english**

where in the book The Importance of Being Earnest does the author make fun of the victorian value of Social Responsibility?

**Chemistry**

We have to conduct a lab experiment for a photochemical reaction. We will be using a redand violet film and filter paper labeled 40W and 60W. On each piece of paper we will add 1 drop of NaCl and AgNO3 and then let it sit under a lamp to see what happens. At the end we will ...

**Chemistry**

ok thank you I apprieciate all of your help!!

**Chemistry**

In the cchemistry lab we conducted an experiment called atomic spectroscopy. We had to find the color, energy, wavelength, and 1/lamda for Hydrogen, neon, and mercury. For hydrogen: red 1.90ev 650nm 1.54e^-3 red 2.02ev 610nm 1.64e^-3 green 2.30ev 545nm 1.83e^-3 for neon: green...

**Chemistry**

1) What is the charge on the ion that Selenium forms in an ionic compound? I am not sure about this. 2) What noble gas is isoelectronic with this ion. I was thinking Krypton because it is a noble gas and it is the closest to Selenium but I am not sure. 3) What other ions are ...

**Chemistry**

ok where do you get those numbers from?

**Chemistry**

for chose 5 Ca is next to K and above Sr so wouldnt Sr be greater?

**Chemistry**

1) A Cobalt (II) ion has the electron configuration ____? and is ____? The answer choices were: [Ar] 3d5 4s2 diamagnetic [Ar] 3d7 paramagnetic [Ar] 3d5 4s2 para [Ar] 3d7 dia None of these I chose [Ar] 3d5 4s2 diamagnetic 2) Choose the corect statement concerning ionization ...

**Chemistry**

Thank you for your help!!!

**Chemistry**

1) What is the atomic # for selenium? 34 2) Write the full electron configuration for selenium following the (n+l) rule? I am not sure what is meant by n+l 3) write the electron configuration, grouping electrons by their "n" values. [Ar]3d10 4s2 4p4 Are these correct...

**Chemistry(Please check)**

Thank you!

**Chemistry(Please check)**

1)For an atom of carbon how many valence electrons are "s" electrons? 2 2) How many are "p" electrons? 4 3)How many (total) electrons in carbon are paired? 2 4) How many are unpaired? 1 Are these correct.

**chemistry**

Based on the nl designation and max # of electrons above, write the electron configuration for carbon. 1s2 2s2 2p2 or [He]2s2 2p2 How many electrons are in the first shell n=1? These are the core electrons for carbon. I think two are in the first shell How many valence ...

**chemistry**

the question then says to expand the above values in the table for all the l values of n=4. Are more possible for n=5? I am not sure what they mean by expand it but I think that there are more values for n=5.

**chemistry**

ok so for n=3 and l value 0 it would be the the nl would be 3s and max electrons would be 18?

**chemistry**

o ok. In my textbook it shows a chart with electron shells and it has the maximum electrons possible for nth shell (2n^2). What does this mean?

**chemistry**

So for the following: 1)n=2 2) l=0 3) l letter= s 4) nl designation= 2s Are numbers 2 and 3 correct?

**chemistry**

o ok i think i understand and what would the maximum number of electrons be?

**chemistry**

write the corresponding subshell leters for the combinations given. Fill in the possible number of electrons for these subshells. 1) n=1 2) l value=0 3) l letter? 4) "nl"Designation 5) Maxium # of electrons the table shows n values of 1, 2,2,3,3,4 with l values of 0,...

**Chemistry**

In the cchemistry lab we conducted an experiment called atomic spectroscopy. We had to find the color, energy, wavelength, and 1/lamda for Hydrogen, neon, and mercury. For hydrogen: red 1.90ev 650nm 1.54e^-3 red 2.02ev 610nm 1.64e^-3 green 2.30ev 545nm 1.83e^-3 for neon: green...

**Chemistry**

In the cchemistry lab we conducted an experiment called atomic spectroscopy. We had to find the color, energy, wavelength, and 1/lamda for Hydrogen, neon, and mercury. For hydrogen: red 1.90ev 650nm 1.54e^-3 red 2.02ev 610nm 1.64e^-3 green 2.30ev 545nm 1.83e^-3 for neon: ...

**Chemistry**

on the x axis was 1/wavelength (nm-1) and the y axis was energy(ev). The line for both graphs of neon and hydrogen was positive. So would I pick two points on the graph to find the slope and then do h=slope/c?

**Chemistry**

In the cchemistry lab we conducted an experiment called atomic spectroscopy. We had to find the color, energy, wavelength, and 1/lamda for Hydrogen, neon, and mercury. For hydrogen: red 1.90ev 650nm 1.54e^-3 red 2.02ev 610nm 1.64e^-3 green 2.30ev 545nm 1.83e^-3 for neon: green...

**Chemistry**

Consider the last electron in B: Values for n,l,and ml of 2,0,0 cannot be used. Why not? so is this the same answer as lithium. The ground stat cant have l=2 since it has no p electrons? Are values of 3,0, 0 allowed? Why or why not? I would say no for the same reason. Are ...

**Chemistry**

What are the n,l,ml,and ms values for the last electron in Be?

**chemistry**

Consider the last electron in Li: Values n,l,ml,and ms of 1,1,0, +1/2 are not allowable. Why not. I do not understand this question. I am not sure what the values for the last electron would be.

**Chemistry**

Electron Configuration: What numerical values of l are possible for n=4. 1,3,5,7 what ae their corresponding letters. s,p,d,f Are these correct?

**Chemistry**

o ok thank you!!

**Chemistry**

Thank you and sorry. Sometimes it does not show up on my computer when someone answers.

**Chemistry**

Write the n, l, ml, and ms values for the first two elements, H and He. H: n=1 l=0 ml=0 ms=+1/2 He: n=1 l=0 ml=0 ms=+1/2 for the first electron for the second: n=1 l=0 ml=0 ms=-1/2 Are these correct?

**Chemistry(Please check)**

Write the n, l, ml, and ms values for the first two elements, H and He. H: n=1 l=0 ml=0 ms=+1/2 He: n=1 l=0 ml=0 ms=+1/2 for the first electron for the second: n=1 l=0 ml=0 ms=-1/2 Are these correct?

**Chemistry**

ok thank you!!

**Chemistry**

For each l value indicate the ml values allowable? l=1 ml=+1, 0, -1 l=2 ml=+2,+1,0,-1,-2 l=3 ml= everything from +3 to -3 l-4 ml= everything from +4 to -4 Are these correct? What are the ms values allowable? These I am not sure about. Is it the number of orbitals?

**Chemistry**

Quantum numbers: What are the n values that are allowed? I put 1,2,3,4, etc. For the first four of these, indicate the l values allowed. n=1 l = 0 n=2 l = 0,1 n=3 l = 0,1,2 n=4 l = 0,1,2,3 Are these correct?

**derivatives**

How do you find the derivative of (6 csc x)/x?

**derivatives**

I know. I just realized that I messed up what goes where when I was doing it myself. My problem is applying it to other problems, esp when i also have to use the quotient or product rule.

**derivatives**

Thanks. My teacher told us we need to use the chain rule in these problems, and i'm having trouble figuring out when and where to use it.

**derivatives**

how do u find the derivative of (csc x)^7 -cos 4x???

**Calc**

to find an arcsin you would just have to memorize the unit circle right? so arccos of -sqrt3/2 is 5pi/6?

**Calc**

oops mixed up 2 questionss haha

**Calc**

How do you do the derivative of an inverse trig function? arcsin (sqrt2/2)??

**Chemistry**

yes thank you i understand the parts for moles of KHP and NaOH. So the mw of KHP was given to me which was 204.44g/mol so for moles of KHP i did 1/204.44 and got 0.004 and then for NaOH i got 0.004 as well. Then for the concentration of NaOH would i do 0.004/0.0145 and 0.004/0...

**Chemistry**

For a chemistry lab the experiment was to carry out an acid-base titration to determine the exact concentration of a sodium hydroxide solution. Two trials were completed and the data collected was: mass of weighing paper, mass of weighing paper + KHP, mass of KHP, initial ...

**Chemistry(Please help, thank you!!)**

Thank you!!

**Chemistry(Please help, thank you!!)**

ok i do not understand at all but thank you for your help.

**Chemistry(Please help, thank you!!)**

SO would it be 27.80 / 10.00?

**Chemistry(Please help, thank you!!)**

Determine the concentration of a NaOH solution if 27.80mL of NaOH is required to neutralize 10.00mL of a 1.00 M H2SO4 solution. (Hint:Review monoprotic vs. diprotic acids.) would I do (27.80)(10)? Thank you for your help!!

**Chemistry(Please help, thank you!)**

ok so for mole of kHP it would be 1/204.44 = 0.00489 g/mol? The volume of NaOH for trial 1 was 14.50 mL and for trial 2 it was 9.90mL. So would it be 39.998 which is molecular mass of NaOH divided by the volume?

**Chemistry(Please help, thank you!)**

For a chemistry lab the experiment was to carry out an acid-base titration to determine the exact concentration of a sodium hydroxide solution. Two trials were completed and the data collected was: mass of weighing paper, mass of weighing paper + KHP, mass of KHP, initial ...

**Geology**

For my final I am to write a paper discussing the following : Select some product produced in your city or state that is made from earth, mineral, or energy resources. One example would be the tar paper used as a building material. (Do not use this example). Prepare a 700- to ...

**Chemistry**

Thank You!!!

**Chemistry**

A concept map was to be created on acids and bases. The concept terms that were given to use were: aqueous solution,bases,acids,ions,weak bases, strong bases, strong acids, weak acids,dissociation, weak electrolyte, strong electrolyte,reaction,salt, neutralization, hydronium ...

**Chemistry(Please help!!)**

For a chemistry lab the experiment was to carry out an acid-base titration to determine the exact concentration of a sodium hydroxide solution. Two trials were completed and the data collected was: mass of weighing paper, mass of weighing paper + KHP, mass of KHP, initial ...

**Science- physics**

Thank you so much! My teacher has NO idea how to teach us anything! I really appreciate your help! Thanks <3

**Science- physics**

How much does a 20ft x 10ft x 8ft swimming pool filled with water weight? Assume the water has a weight density of 62 lbs/ft3. I know the answer is 99,200 pounds but how do I get that answer? Thanks<3

**Science- physics**

An aluminum bar weighs 17 pounds in air. How much force is required to lift the bar while it is immersed in gasoline? The weight of aluminum is 170 pounds/ft3 and that of gasoline is 42 pounds/ft3. I know that the answer is 12.8 pounds but how do I get to that answer? Thanks<3

**Science- physics**

An iron anchor weighs 250 pounds in air and has a weight density of 480 lbs/ft3. If it is immersed in sea water that has a weight density of 64 lbs/ft3, how much force would be required to lift it while immersed? I know the answer is 217 pounds but I need help on trying to get...

**Science- physics**

A balloon weighing 80 kg has a capacity of 1200 m3. If it is filled with helium, how great a payload can it support? The density of helium is 0.18 kg/m3 and the density of air is 1.30 kg/m3. Express your answer in Newtons. I know the answer is 12, 400 Newtons I just don't ...

**Science**

The formula for density is... density= mass/volume So yes you would divide 6773 g/500 mL!

**Chemistry**

For my first trial KHP was 1.00g and for the second trial it was the same. So to find moles of KHP would I do 204.44g/mol X 1/1g which would be 204.44g/mol?

**Chemistry**

For a chemistry lab the experiment was to carry out an acid-base titration to determine the exact concentration of a sodium hydroxide solution. Two trials were completed and the data collected was: mass of weighing paper, mass of weighing paper + KHP, mass of KHP, initial ...

**Chemistry**

Write a net ionic equation for the overall reaction that occurs when aqueous solutions of potassium hydroxide and carbonic acid are combined. KOH + H2CO3 = KCO3 + H30 K^+(aq) + OH^-(aq) + h2CO3 (aq) = K^+(aq) + CO3^2+(aq) + H3O(aq) Is this correct so far?

**science**

If a scientist changes two variable he/she would not know which change would increase or decrease his/her theory or hypothesis. The scientist wants to determine one thing that changed it the most not two things!

**Ap chem**

When .4000 g of CH4 is burned in excess oxygen in a bomb calorimeter that has a heat capacity of 324, the temperature increases 6.795 degrees celsius. How much energy is released? (in kJ/mol CH4)

**Science**

A container with equal sides of 8 cm is filled with 1200g of fluid. What is the force in Newtons on the bottom of the container?

**math**

a rectangle has an area of 330m^2 , one side is 7 m longer than the other what are the dimensions of this rectangle

**Math**

Simplify a)(1-ã3)(2+ã6)(5+ã2) b) -5ã45+ã52+3ã125

**5th grade math**

seventy five multiplied by one hundred twenty

**science**

how long does a teenager need to sleep at night?? my teacher asked this question and if you get it right, you get 2 extra points on a test, so please help me!!

**Physical Education**

P.E. is a time to achieve physical activity. To obtain a healthy living style you should exercise for 60 min a day. Most kids/teenagers would probably not chose to do that therefore schools decided to include that needed exercise in the kids' school time.

**Spanish**

I'm in the 8th grade and I have been taking French now for about a 1 1/2. I have learned many things and it is probably the easiest way to learn about another country! salut! (thats goodbye in french btw)

**Chemistry**

The empirical formula for Brilliant Blie dye is C37 H34 N2 O9 S3 Na2, and the formula weight is 792.86 g/mol. How would you prepare a 4.73 X 10^-6 M solution of Brilliant Blue dye? How many grams of the dye do you need to add to a 1.00 L of water to make this solution? I have ...

**Chemistry**

To calculate the percent error you would use the error in measurement divided by accepted value times 100 correct? So for an experiment in which you had to find the concentration of a dye in a powdered drink solution, to find the percent error would you use the number you ...

**Chemistry**

A sample of 30.0 mL of sulfuric acid solution was titrated with 0.720 M KOH. It was found that 46.9 mL of the base was needed to neutralize the acid. What is [H2SO4]? would you do (30.0)(0.720) / 46.9 ?

**Chemistry**

What volume of o.410 M HNO3 would you need to neutralize 18.75mL of 0.376M Ba(OH)2? Would you do (0.410)(18.75) / 0.376? Or (0.410)(0.376) / 18.75