# Posts by Joshua

Total # Posts: 702

**Chemistry/please check**

Calculate the amount of heat in kilojoules reased when 50 of steam at 125 C are converted to 50 grams of ice at -125 C. AHsteam = m * Cp steam * At q1= 50g * 4.184 J/g C * (125-100)C= 5.23 x 10^J q2= m * AH 50g * 5230 J/g = 2.61 x 10^5 J q3= 50g *4.184 J/g C * (100-0)C= 2.10 ...

**chemistry**

is this the right anser? for this problem please let me know thanks calculate the amount of heat in kilojoules released when 50 grams of steam at 125 C are converted to 50 grams of ice at -125 C so 50 grams of H2O Ti= 124 C Tf= -125 C q=? J=? q=m *Cp * At J= 50g * 4.184J/g C...

**chemistry**

oh i see m ok thanks

**chemistry**

if so then the solution will be Delta T= Kf * M T= 7.0 C/m * O.474mol/g T=3.32 C The freezing point of the solution will be 5.7 C - 3.32 C = 2.38 C please let me know if this is correct? please

**chemistry**

from the texbook K(f)= 5.12 C/m but from the exercise is 7.0 C/m which one should i use to solve fro the freezing point? please help

**chemistry**

thansk

**chemistry**

i need to know if I am in the right tract please let me know...I am calulating the molality of the following exercise so I could be able to apply the formula T=Kf * molality calculate the freezing point of a solution containin 12.2 grams of benzoic acid, dissolved in 250 grams...

**Chemistry**

calculate the freezing point of a solution containing 12.2 grams of benzoic acid, dissolved in 250 grams of nitrobenzene. the freezing point of nitrobenzene is 5.7 celsius and its freezing point depression constant is 7.0 celsius/m. please help

**Chemistry**

thanks I think i got it now

**Chemistry**

Calculate the amount of heat in kilojoules released when 50 grams of steam at 125 C are convert to 50 grams of ice at 125 C please help

**Chemestry**

where you got the 7.7 from? and how you calculate the molality for it. I am stuck please help

**History**

I just have one more question on this matter; does the Congress's power to declare treason to a person/ establish inferior courts in states pertain to the federal territories as well?

**History**

Thank you for your help.

**History**

What authority does Congress have over other states according to Article III of the Constitution? Over federal territories?

**Math**

Thanks drwls for the good explanation =)

**Math**

Hi drwls, Just wondering, does the word "under" in the question influence the question at all? Thanks for your reply! =)

**Math**

Hi guys, In the question "It is given that P (0, 3), Q(7, 5), R(9, -2) and S are vertices of a square. A circle A passes through the points P, Q, R and S. Find the equation of this circle. Hence or otherwise find the equation of circle B which is the image of A under the ...

**Writing prompt**

Hi Jherica Holland, You have posted several questions regarding the 18th century. What I suggest is for you to search "the 1800's" on Google. There are some personal recounts which you could use as reference material. Hope I helped. Thanks! :)

**Chemistry**

Hi Bo, we have several indicators, including litmus, universal indicator, bromothymol blue, methyl orange, and screened methyl orange. There are many, and the list can go on forever, but these are most commonly used. The best, in my case, would be universal indicator or litmus...

**writeing promot on the 1800's**

O_o didn't consider that haha :)

**writeing promot on the 1800's**

Hi brittany lasseigne, what do you need help with? There are many points of comparison you could consider jotting down. You could try to talk to grown ups who have lived through the 1800's as children. Here's some starting material for you (Please do not copy, this is ...

**Math Calculus**

Thanks ^^

**Math Calculus**

Hi, I don't have any question specifically but I'm very confused on this. In integration to find area under/above a curve, when do you integrate: 1) with respect to y 2) with respect to x 3) using x coordinates 4) using y coordinates Thanks for your help! :)

**chemistry**

Hi Anonymous, Truthfully speaking I don't know much about ozone cracking. However, seeing that no one has answered your query for almost two hours, I will try to help. The definition of ozone cracking as stated in Britannica Encyclopedia is as such: "Atmospheric ozone...

**chemistry**

Hi Lili, I'll try this one. You could add silver carbonate to the solution. A white precipitate is produced, while a colorless, odorless, gas is evolved which produces a white precipitate in limewater (calcium hydroxide). Hope I helped! :)

**Wellness, puberty**

might not*, spelling error.

**Wellness, puberty**

Hi Max, well, in short, we need the knowledge for adulthood after marrying etc. Also, this knowledge is classified as general knowledge, some might need it, some might now :) Though most do, like how many people are reliant on common knowledge

**math-3rd grade**

together with 1100 + 1600, 1100 - 500, and I'm not sure if you also want to include those with negative answers..

**math-3rd grade**

Oops, missed out some equations such as 500 + 1600, sorry about that

**math-3rd grade**

Hi elaine, Yup, that is all correct. Well done!

**Math**

Hi Tina, A palindromic number is a symmetrical form, in this case, xyx, where x has to be 2 as the number is between 200 and 300. We'll ignore the y to move on to finding the x. Create two numbers where the difference of the hundreds place = 2. For example, 9y9 and 7y7. Or...

**calculus**

Hi Meghan, If you differentiate a constant (i.e. any number, fraction or yeah...a constant), you always get 0. Hope I helped :)

**Math**

You're welcome ^^ :)

**Math**

Okay, we'll do it by completing the square. :) From 3x^2 + 4x = 224, x^2 + 4/3 x = 224/3 x^2 + 4/3x + 4/9 = 224/3 + 4/9 (x+2/3)^2 = 75/1/9 x + 2/3 = square root of 75/1/9 x + 2/3 = 8/2/3 or -8/2/3 x = 8 or -9/1/3( Not applicable as positive integer cannot be a negative ...

**Math**

Your formula is correct. Assuming you add up the 3x and x to form 4x, you have to use the general solution of a quadratic equation. Do you know how to use it? =) By the way, x should be 8 if you use it right.

**Mathematics**

Thanks for the help =) Clear and detailed explanation.

**Mathematics**

Hi there, Can someone help me with the question: "Prove that the value of 7sinx +3cos2x cannot be greater than 5/1/24 for all values of x between 0 degrees and 360 degrees" Thanks lots. =) I've already simplified 7sinx + 3cos2x into (2sinx-3)(3sinx+1).

**5th grade math**

i am a number less than 10.my hundreds digit is 3 more than my thousands digit,my tenths is 2 less than my hundreds and my ones is the sum of my tenths and hundreds digits.what number can i?

**rounding decimals**

whay is the difference between rounding decimals to the greatest to the nearest whole

**ecology**

WHICH WEATHER SITUATION WILL BE THE LEAST COMFORTABLE FOR A LONG DISTANCE RUNNER? A.20* CELCIUS (68f) WITH RELATIVE HUMIDITY OF 40% B. 20* CELCIUS (68f) WITH RELATIVE HUMIDITY OF 90% C.25* CELCIUS (77 f) WITH RELATIVE HUMIDITY OF 90% D.35* CELCIUS (95 f) WITH RELATIVE HUMIDITY...

**biology**

what is the the equation for photosynthesis?

**Math**

Differentiate population from sample

**geometry**

what are the problems?

**geometry**

What are if then statments .Ill need examples please .its for a project .

**HELP WITH MATH**

Sorry the caps lock was on. Can you help me with this pre calculus question. I'm not quite sure how to do this. Here are the instructions. Find the area between each curve and the x-axis for the given interval: y=2x^2+x+1 from x=3 to x=6

**chemistry**

Suggest a type of reaction and the conditions required to breakdown polyamides into their monomers.

**Psychology-Opinions wanted**

i love psychology

**physics**

What is the wavelength of a proton traveling at a speed of 6.87 km/s

**trig**

What kind of reflections are the following trig functions? y = 3cos(x-1) y = sin(-3x+3) y = -2sin(x)-4

**trig**

What kind of reflections are the following trig functions? y = 3cos(x-1) y = sin(-3x+3) y = -2sin(x)-4

**trig**

y = 3cos(x-1) Shift along x: Shift along y: Kind of reflection:

**us history**

Thanks, much appreciated, very nice of you to look.

**us history**

Is there any way someone can provide me with either a synopsis, or a link to a synopsis to the lincoln steffens book The struggle for self-government? Thanks

**math**

s^2 - s - 6 What you're looking for is a number that when you multiply it, it equals -6 and when you add them it equals -1. these values -6 and -1 are derived from the equation. so number could be --> -/+ 3, -/+ 2 but since there's only one way of getting -1 when ...

**Math**

( 2 3/4 miles ) / ( X feet) = ( 1 mile)/ ( 5280 feet ) then cross multiply (2 3/4 mi)*(5280 feet)= (x feet)(1 mi) (2 3/4 )(5280) = x feet that equals your total feet for 2 3/4 miles.

**math**

7,2 ---> 2,7 5,4 ----> 4,5 1,8 ----->8,1 9,0 -----> can't be reversed because it doesn't become a two digit number. 3,6 ----->6,3 ----------------------------------- all these two digit numbers add up to 9, and if reversed, you should subtract 72- 27= ...

**chemistry**

Match the correct mole ratio to the substances in the reactions below. carbon monoxide to iron in the reaction: Fe2O3 + CO ==> Fe + CO2 water to manganeese(II) chloride in the reaction: HCl + MnO2 ==> H2O + MnCl2 + Cl2 sodium to oxygen in the reaction: Na + O2 ==> ...

**geography**

how do i find countries with rank classes?

**chemistry**

When 0.627 g of Ca metal is added to 200.0 mL of 0.500 M HCl(aq), a temperature increase of 102C is observed. Assume the solution's final volume is 200.0 mL, the density is 1.00 g/mL, and the heat capacity is 4.184 J/gC. The molar heat of reaction, H rxn, for the reaction ...

**math**

2. since you want to know for 20 days, how much gas you waste, 20*( 1 1/2) = 30 So , you waste 30 gallons of gas in 20 days, How much money do you spend on 30 gallons of gas. 30*($2)= $60 for 30 gallons of gas which covers 20 workdays)

**math**

1. its a basic subtraction question. (3/4)-(1/2)=1/4 you subtract because he sold it.

**math**

(3/4)^(-1). Just switch the fraction to 4/3 , because its the whole fraction raised to -1. if ( 3^(-1) ) / 4 ==> 1/(3*4)=1/12

**math**

-7^ (-2), put it divided by 1. -1/(7^2) when you place the exponent to the denominator, change the sign, same goes if you have a negative exponent on the denominator, bring it to the numerator and change the sign. -1/49

**algebra**

(m+5/6)= -19 (m+5/6) *6 = -19 *6 (m+5) -5= -114 -5 m= -119

**pre- algebra**

(5t-9/ 4 ) = 14 5t-9 =14*4 multiply 4 to both sides, and it cancels the 4 on the left side. 5t-9=56 add 9 to both sides, and it cancels on the left side. 5t=56+9 5t=65 divide by 5 on both sides t= 13

**pre- algebra**

Do have trouble finding t?

**pre- algebra**

30= new racket 30= 3x-6, where x=old racket so x=12, old racket cost 12 dollars

**criminology**

what are the three major kinds of crime statistics used by criminologists? What are the advantages and disadvantages of each measure of crime? What kinds of questions about crime does each measure address most usefully?

**Math adding fractions**

i need help!

**Japanese - translate & construct sentences**

Wow! Thank you so much^^

**Japanese - translate & construct sentences**

I need help translating the following into japanese. -Clan of the Shadow. -Village of the Shadow. -Hidden Village of the Shadow. -Country of the Shadow. -Land of the Shadow. -Second Royal Family of the Village of the Shadow This is what I have so far: #Shadow: kumori, kage, ...

**Japanese (extramural: linguistics/culture/history)**

|SraJMcGin| No problem!^^ Thank you very much for those links! Very interesting sources.

**Japanese (extramural: linguistics/culture/history)**

|Anonymous| Oh, you're right. Thanks mate! Good luck to you too. |drwls| My apologies^^ ... but the statement is meant to be taken in a personal sense (nothing foreign for me) ... Impressed that you feel so strongly about me homeland^^ Japan, very very interesting indeed...

**Japanese (extramural: linguistics/culture/history)**

...sorry for any of the grammatical errors... kinda in a hurry today^^

**Japanese (extramural: linguistics/culture/history)**

Hallo, my name is Joshua. I'm currently doing my matric in south africa, which is most unfortunate, because south africa doesn't have much to offer in terms of "foreign languages/culture." (Moving to england in a month. Perhaps it has more to offer^^) I am ...

**Algerbra**

w=42.5

**Askk**

What is the worlds tallest man

**History**

Was pope gregory justified in excommunicating Henry? explain?

**History**

What is excommunication? what role did it play in the struggle between popes and kings?

**History**

How does the hierachy of the catholic church compare to the hierachy of feudal society in western europe?

**History**

What aspects of european society did the church dominate from 1100 to 1300?

**Biology**

-6.86 bars

**Physics 221**

1. throughout a time interval, while the speed of a particle increases as it moves along the x axis, its velocity and acceleration might be: A. positive and negative, respectively B. negative and positive, respectively C. negativa and negative, respectively D. negative and ...

**Physics 221**

An object starts from rest at the origin and moves along the x axis with a constant acceleration of 4m/s^2. Its average velocity as it goes from x=2m to x=8m is: A. 1m/s B. 2m/s C. 3m/s D. 5m/s E. 6m/s An object is released from rest and falls a distance H during the first ...

**Algebra**

How do you calculate the area of a rectangle. area of a rectangle is length x width.

**Math**

On a grid with points R(-2,-6)& S(3,4), what is the slope of line RS? I don't know how to find the slope. Thank you. The formula for a straight line is y = mx + b m is the slope and b is the y intercept. One way is to plug in the two sets of points listed in the problem ...

**Computer Science**

Describe Operating systems theory and configuration at the Unix kernel/Windows registry level Describe standard operating system services (RPC, NetBIOS, etc) Describe File storage, management, and security shemes Describe command line administration of UNIX/Windows Describe ...

**Ancient Civilization**

What is a mixture of sand, lime and water and used as lubricant to move stones in ancient egyptian civilization? Slurry is a nice word.

**ancient civilization**

what is a mummy shaped amulet that held farm tools.....it starts with the letter S? Thank you for using the Jiskha Homework Help Forum. It's interesting to note that this was a crossword puzzle word! Here's the answer: These statuettes would be placed in a tomb along ...

**Ancient civilization**

What is a translucent stone used in floor slabs in ancient egyptian civilization? If you'll go to http://www.google.com and enter translucent stone egyptian, you'll find the answer. =) http://touregypt.net/magazine/mag06012001/magf5.htm

**5th Grade Math**

I need help on how to use an equation to graph? Here is an example from the text book. y=x-4 example shows x= -2 -1 1 2 y= -6 -5 -3 -2 I want know how did they show this relationship.

**math**

ok, but what happened to the letters? don't they remain part of the problem? also, how does 15k/20k reduce to 4/5? thanks for your help. joshua 15k/20k should reduce to 3/4 because you can take a 5 out of 15 and be left with 3 and take 5 out of 20 and be left with 4. The ...

**where did bob go?**

can anyone simplify and multiply the rational expressions 10m/11p x 44p/20k x 15k/8m? and then explain it to me? have patience.

**math**

10m/11p.44p/20k.15k/8m we are multiplying and dividing rational expressions. can ne1 help? I have no idea what you need. Your first line makes no sense. i know, it doesn't make any sense to me either...it's fractions 10m/11p times 44p/20k times 15k/8m. we have to ...

**Religion**

In the Christian religion,why were ashes originally sprinkled on the top of people's heads on Ash Wednesday instead of on the forehead? This site gives the history of the use of ashes on Ash Wednesday. http://www.wf-f.org/AshWed.html#anchor2360581 http://www....

**chemistry**

which atom has a higher potential energy? neon or flourine

**calculus**

Constant annual percentage growth The function gives the value of a home in dollars in the year 2000 + t. Find the constant annual percentage change in the value of the home. Give appropriate units with your answer. Again, I'm not sure what function is being referred to ...

**calculus**

writing an exponential equation The function gives the value of a home in dollars in the year 1980 + t. Write an equation that can be used to determine the year in which the value of the home reached $100,000? Use ^ to denote an exponent. Do not solve the equation and do not ...

**calculus**

Evaluating an exponential function The function gives the value of a home in dollars in the year 1980 + t. What was the value of the home in 1988? Round your answer to the nearest whole dollar amount and give units. You would evaluate for t=8. The units should be dollars. Your...

**calculus**

Consider the exponential function . Which of the following best describes the the graph of g? a. Concave up and increasing b. Concave up and decreasing c. Concave down and increasing d. Concave down and decreasing The rules are +constant, concave up, - constant concave down. ...