Thursday
April 17, 2014

Posts by smiley


Total # Posts: 81

science gr.8
A kicker strikes a ball with a strong force. a) Explain the evidence that shows the ball is not filled with liquid? b) Describe what is happening to the particles inside the ball? * chapter is about forces and pressure*

Science data
well not really because graphs are used to display your data, and just the date would be considered as ur info not the display.

science gr.8 science fair topic ideas
what are some ideas for science fair projects gr.8?!?! and please give an experiment with it thank u!!

socials gr.8!!
what contributions has the arab society made to the canadian society?!? ANSWER IN COMPLETE SENTENCES PLEASE AND EXPLAIN!!!!

Science
What is the difference between a controlled experiment and a natural experiment?

physics
The current-density magnitude in a certain circular wire is J = (2.75 × 10 10 ⁄ )r 2 , where r is the radial distance out to the wire’s radius of 3.00 mm. The potential applied to the wire (end to end) is 60.0 V. How much energy is converted to thermal energy ...

poems
does anyone know a poem about seashores and it has to be aroung grade 6 level thank u?

Math
u measure

language arts/math
what is an irregular polygon. what is congruent. what are corresponding angles. what are corresponding sides. FULL SENTENCES PLZZZ!!!!

life orientation
pollution, landfills, animals homes destroyed, less space on earth,

spanish
i think its nombre

Health: 6th grade
do u mean sling?

language arts
can anyone plz tell me a gud story if u were evr a shape for example this wut my friend her shape was a rectangle she wrote that the rectangle is going to apply for a job and the job is of an ice cream cart meaning like the ice cream cart and at the end the circle gets chosen ...

science
what are the characteristics of plants and animals

calculus
y'=xy/2ln y how do you solve the differential equation by seperation of variables

SCIENCE!!!!!!!!!!
a. Find the speed required to throw a ball straight up and have it return 6 seconds later. Neglect air resistance. b. How high does the ball go? Please Help!! Thanks!! :)

SCIENCE!!
a. Find the speed required to throw a ball straight up and have it return 6 seconds later. Neglect air resistance. b. How high does the ball go? Please Help!! Thanks!! :)

SCIENCE!!
a. When a ball is thrown straight up, by how much does the speed decrease each second? b. After the ball reaches the top and begins its return back down, by how much does its speed increase each second? c. Compare the times going up and coming down. Please Help!! Thanks!! :)

English
Name a database that would help you with current events. Please Help!! Thanks!!

English
What is the subject covered in the encyclopedia with the call number 150 ENC? Please Help :P Thanks!! :))

math
Well - Two fractions equivalent to 2/5: 4/10 an d6/15. - Two fractions equivalent to 7/11: 14/22 and 21/33. - Two fractions equivalent to 150/325: 300/650 and 450/975. To solve this you should of multiplied each fraction by a number (E.G. 2/2) For 2/5, I did 2/5*2/2= 4/10. I h...

math
What is a g

Earth science
what is the material between 2900 kilometers and 5200 kilometers below earths surface inferred to be

Judges
Explain possible consequences of ineffectiveness

Chem help
ln(K1/K2)=(∆Horxn/R)((1/T2)-(1/T1)) ln((6.5x10^-2)/K2)=((-49.5 kJmol^-1)/R)((1/(250+273.15))-(1/(100+273.15))) That's it! Just solve for K2. Don't forget that your R must have the units of kJ/molK. Hope this helps. Cheers!

chem
you have 157.5 mmol of AgNO3 and 243 mmol of MgCl2. From the balanced chemical equation, 1 mol of MgCl2 would consume 2 moles of AgNO3. It would then require 315 mmol of AgNO3 to completely consume the MgCl2. Therefore, AgNO3 is the limiting reactant and it would dictate how m...

Chem.
Its name is methyl ethanoate. First, you must find the carboxylate part. In your case, this is ethanoate. Next, determine what is attached to the O (not the one double bonded to C) of the carboxylate. In your case, this is CH3 and you would call this methyl. Lastly, combine th...

Math (PLEASE HELP!!)
Through how many degrees does the hour hand move... 1. In 3 hours? 2. In 2 hours?___________ 3. In 1 hour?___________ 4. In 1/2 hour?____________ 5. In 10 minutes?___________ Please Help!! Thank You!!

Math (PLEASE HELP!!)
Through how many degrees does the minute hand move... 1. From 10:00 to 11:00?_______________ 2. From 4:00 to 4:30?_______________ 3. From 6:00 to 6:15?_______________ 4. From 9:00 to 9:05?_______________ 5. From 3:00 to 3:01?_______________ Please Help!! Thank You!!

riddle
argh!!

riddle
Here is another one: J,F,M,A,M,J,J,A,.....

riddle
Hint: The answer is not "E".

riddle
what comes next? O,T,T,F,F,S,S,E,......

English
I think he did set more than 1 0r 2 records, right?

English
Power & greed are sometimes the main cause of war because: Power: You are strong & want to gain more land, food, things, etc... Definition: The possession of control or command over others; authority. Ability to do or act; capability of doing or accomplishing something. Greed:...

English
Actually, I wanted to use the sentence below: During May 15-July 17, 1941, DiMaggio held the longest consecutive game hitting streak (56 games). Does that make sense? **It makes more sense because it was during that year, not between it. Thanks!!

English
Which sentence is better? 1. Between May 15, 1941-July 17, 1941, DiMaggio held the longest consecutive game hitting streak (56 games). 2. Between May 15-July 17, 1941 DiMaggio held the longest consecutive game hitting streak (56 games). Please Help!! Thanks!!

English
Which sentence is better? 1. On May 15, 1941-July 17, 1941, DiMaggio held the longest consecutive game hitting streak (56 games). 2. On May 15-July 17, 1941, DiMaggio held the longest consecutive game hitting streak (56 games). Please Help!! Thanks!!

English
which sentence is correct, #2 or #3? SraJMcGin chose #2 & Ms. Sue chose #3. I do not know which one to choose..... HELP!!

english
hi

psychology
hi

Chemistry------DrBobb..
hi

Ionic Crystal Structures
How did you get that answer then?

spelling
I'm sorry yes. could you tell me what is a non characteristic of region? Please help, thank you.

spelling
I am doing a Frayer model and my spelling word is region. That is a non-characteristic for region? Thank you for your help.

Math
Julia wants to build another garden wall, 10 bricks long and 3 bricks high. Can she build it with red and white bricks, so that no two bricks of the same color are next to each other? r w r w r w r w r w w r w r w r w r w r r w r w r w r w r w I say yes. Could you help me if t...

Math
Ray is setting the table for a birthday diner.He needs to set 12 places at a round table.he has 3 different kinds of plates:white plates; blue plates; and gold plates.How can he set the table so that no two of the same kind of plates are next to each other? Thank you for your ...

Math
A trapezoid, parallelogram, and rhombus. they all have 45 degrees angles.

Math
a parallelogram.

sose
what is the meaning of life?

Chemistry
its wrong!

CHEMISTRY
What is the effect of cyclohexane as the solvent in the electrophilic aromatic substitution of acetanilide by bromine?

chemistry
What is the effect of using cyclohexane as the solvent in the bromination of acetanilide?

chemistry
Why can't we add charcoal to benzoic acid in purification by sublimation

analytical chemistry
"experiment: spectrophotometric determination of the acid dissociation constant of methyl red" 1. Why is pH plotted against log([MR-]/[HMR]) to get the pKa of methyl red? 2. Why is it right that HMR has a pH equal to 2 and MR- to have a pH equal to 8?

chemistry
"experiment: spectrophotometric determination of the acid dissociation constant of methyl red" 1. Why are matched cells used in the experiment? 2. Why is pH plotted against log([MR-]/[HMR])? 3. Why is it right that HMR has a pH equal to 2 and MR- to have a pH equal t...

chemistry
Why is it important that the sequence of addition of reagents be followed? What could possibly go wrong when this is not followed? Reagents added: 1st: Fe3+ solution 2nd: 2.00 mL 10% NH2OH-HCl (hydroxylamine hydrochloride) 3rd: excess 0.20% 1,10-phenanthroline 4th: 1.00 mL HOA...

chemistry
Why is it important that the sequence of addition of reagents be followed? What could possibly go wrong when this is not followed? Reagents added: 1st: Fe3+ solution 2nd: 2.00 mL 10% NH2OH-HCl (hydroxylamine hydrochloride) 3rd: excess 0.20% 1,10-phenanthroline 4th: 1.00 mL HOA...

chemistry (spectrophotometry)
I'm sorry but I still don't understand the concept of spectral analysis and the baseline. What does these words mean and what are they for? I'm confused... Note: the experiment determines the concentration of iron in iron(II) phenanthroline by spectrophotometry.

chemistry
Why is an Fe3+ solution instead of an Fe2+ solution used in calibrating the spectrophotometer? Note: hydroxylamine hydroxide is added to the Fe3+ solution then 1,10 phenanthroline is added to the solution after the addition of hydroxylamine hydroxide. After these additions, a ...

chemistry
Why should an Fe3+ solution be used in calibrating the spectrophotometer for the spectrophotometric determination of iron in Fe2+ complexes?

additional question
what is apectral scanning? I really don't have an idea on this. As for the baseline, we indicated a range of 350 nm to 600 nm in the spectrophotometer and found that lambda max is at 510.4 nm. What then is the significance of the baseline?

chemistry
1. Why Beer's law is expressed in terms of absorbance instead of transmittance? 2. What is the significance of spectral scanning? 3. What is the importance of the baseline?

chemistry
In experiment concerning potentiometric determination of puriy and Ka of KHP, we obtained an experimental pKa of 5.04 and when compared with the theoretical pKa of 5.51, we obtained a % relative error of 192%. Could this error mean that a cerain impurity in the KHP sample effe...

chemistry
Based on the experimental data, I was able to calculate the experimental pKa value which is 5.04 and the literature value of the pKa for KHP is 5.51. If I would be computing for the relative error between the two pKa's it would be 8.52994555%. But then, what i need is the ...

chemistry
Based on the experimental data, I was able to calculate the experimental pKa value which is 5.04 and the literature value of the pKa for KHP is 5.51. If I would be computing for the relative error between the two pKa's it would be 8.52994555%. But then, what i need is the ...

chemistry
what does it mean if I got a % relative error that is higher than 100%? - would it mean that I did the experiment erroneously?

chemistry
The phosphorus in a completely dried fertilizer sample weighing 0.4498 grams was precipitated as MgNH4PO4*6H2O. The precipitate weight was determined to be 236.8 mg and ignited to Mg2P2O7. The weight of the ignited precipitate was 268.9 mg. Calculate the percent phosphorus. My...

chemistry
So, the moisture content (as received) is ((0.5117-0.4998)/0.5117)* 100 = 2.326% and the the moisture content (dry basis) is ((0.1*0.4998)/0.5117)*100 = 9.767% and when the sample is completely dried, it would weigh 0.4998-(0.1*0.4998) = 0.4498 Am I right?

chemistry
Please help me through this problem... A 0.5117 gram fertilizer containing phsphorus was oven dried. The weight of the dried sample is 0.4998 grams. However, 10% moisture is still retained in the sample. Calculate the moisture content in the sample in as received and dry basis...

chemistry
Please help me with my formal report on "Potentiometric Determination of the Purity and Dissociation Constant of Potassium Hydrogen Phthalate" Please give me links to websites that could be used for my reference... In addition, please do suggest books that discuss po...

chemistry
Again, from my previous question about gravimetric analysis... Why can't NH4Cl be used as a substitute for NH3 in precipitating MgNH4PO4*6H2O? Please critique my thought: I found out that a precipitate is more soluble at lower pH and since NH4Cl acidic, it will cause the p...

chemistry
In precipitating magnesium ammonium phosphate, why can't NH4Cl be used as a substitute for NH3? Isn't pH critical? The solubility is vastly different at pH 9 versus pH 4. In addition, how do you obtain NH3 from NH4Cl? The NH3 is for pH adjustment as Bob Pursley writes.

chemistry
Experiment: Gravimetric Determination of Phosphorus in Fertilizer Samples 1. Can NH4Cl be used as a substitute to precipitate the phosphorus in the sample? Why or why not? - I think, NH4Cl can be used although I'm not quite sure if Cl- ions have some effects to the precipi...

chemistry
experiment: Gravimetric determination of moisture in fertilizer samples 1. What are the advantages of weighing by difference to direct weighing when using an analytical balance? 2. Why are the samples grinded before drying in the oven? Weighing by difference minimizes errors i...

chemistry
1. What are other methods of moisture determination besides oven drying? 2. During the drying of samples, the weight is considered constant when the last two weights are within ± 0.0003 grams. What is the reason for this? For #1, here is a site for you to read. (Broken ...

chemistry
Topic: Iodometry 1. the reason why the Cu2+ solution has to be titrated immediately after addition of KI - I thought, because if allowed to stand for a long time, iodine will volatilize and a change in concentration of iodine will occur...is this right? Please correct me if I&...

chemistry
Topic: Iodometry 1. the reason why the Cu2+ solution has to be titrated immediately after addition of KI Answered above.

chemistry
Topic: Iodometry 1. The importance of precipitating the Cu2+ ions using NH3 and redissolving it with acetic acid 2. What are other means of detecting endpoint in iodometry aside from adding starch indicator 1. A pH that is too low leads to excessive oxidation of iodide ion to ...

chemistry
What is an aliquot factor? It is a whole divisor. For instance 5 is an aliquot factor of 15, and 15 is an aliquot factor of 150. I'm sorry, but I don't seem to understand it. For example, how do you get the aliquot factor of 50? 2, 5, 10, 25 would be aliquot factors of...

chemistry
Where can I find the answers to these questions in my text, "fundamentals of analytical chemistry" by skoog, west, holler and crouch. 1. Why is acetylsalicylic acid analyzed using back titration? 2. Discuss the importance of simmering the tablet in the NaOH solution ...

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