Saturday

February 25, 2017
Total # Posts: 1,992

**Chemistry**

Thanks for the help earlier My question Silicon tetrachloride (SiCl4) can be prepared by heating Si in chlorine gas: Si + 2Cl2 yields SiCl4 In one reaction 0.507 mole of SiCl4 is produced. How many moles of molecular chlorine were used in the reaction? Ok is it makeing ...

*July 3, 2010*

**Chemistry**

I know mathematically I can write chemical reactions this way but in chemistry can I if now why? 2K + 2(H20) yields 2KOH + H2 2(K + H20) yields 2KOH + H2 can I also do this if not why? 2(CO) + O2 yields 2(CO2) O(2C + O) Yields 2(CO2) I don't see why I cant do any of these ...

*July 3, 2010*

**Chemistry**

I have realized I don't understand Avagado's number at all My book shows me this diagram instead of just providing a simple formulas that makes no sense at all here is what I have made sense of so far (6.022 x 10^23 atoms/mol)(mass of element) = molecular mass were ...

*July 3, 2010*

**Chemistry**

What is wrong with or ambiguous about the phrase "four molecules of NaCl" I really don't understand my textbook says in the back that it is an ionic compound so I guess that its not really a molecule then I don't understand...

*July 2, 2010*

**AP Biology**

I got a question that comes from the 1990 released test #61 that I'm completley lost on 61. In a population that is in Hardy-Weinberg equilibrium, the frequency of a recessive allele for a certain hereditary trait is 0.20. What percentage of the individuals in the next ...

*July 2, 2010*

**Public High School AP Biology**

I got a question that comes from the 1990 released test #61 that I'm completley lost on 61. In a population that is in Hardy-Weinberg equilibrium, the frequency of a recessive allele for a certain hereditary trait is 0.20. What percentage of the individuals in the next ...

*July 1, 2010*

**physics**

danks 4 includN units kid refuse to solve w/o dem sorry

*July 1, 2010*

**Chemistry (algebra I problem)**

I feel really dumb because I cant figuer out this simple algebra I problem... 84. The diameter of a copper (Cu) atom is roughly 1.3 x 10^-12 m. How mnay times can you divide devenly a piece of 10-cm copper wire until it is reduced to two separate copper atoms? (Assume there ...

*June 28, 2010*

**Public High School AP Biology**

I got a question that comes from the 1990 released test #61 that I'm completley lost on 61. In a population that is in Hardy-Weinberg equilibrium, the frequency of a recessive allele for a certain hereditary trait is 0.20. What percentage of the individuals in the next ...

*June 22, 2010*

**Chemistry**

What is the pH of a 0.42 M NH4NO3 aqueous solution? What is the percent ionization?

*June 20, 2010*

**Chemestry**

What is the pH? 1.6 x 10^(-5)?

*June 19, 2010*

**Algebra**

Thanks!

*June 18, 2010*

**Algebra**

Is this correct? If not can you please tell me what steps I did wrong? Thanks! The hydrogen ion concentration of milk is about 1.6 x 10^-7 moles per liter. Find the pH. pH = -log [H+] pH = -log[1.6 x 10^-7] pH = -(-7.204119983) pH = 7.2 The pH balance of the milk is 7.2

*June 18, 2010*

**Calc**

I'm kind of rusty on my calc here... ok ther's a graph of velocity vs time w/ velocity in m/s and time in seconds were time is of course the x-axis k I'm asked to describe how the velocity changes over the timer interval in this interval the graph consists of three...

*June 17, 2010*

**Algebra**

It is actually for an Intermediate Algebra class. Logitharims.

*June 17, 2010*

**Algebra**

The hydrogen ion concentration of milk is about 1.6*10^-7 moles per liter. Find the pH.

*June 17, 2010*

**Calculus**

How to prove this (e^(2^-1 i3pi) - e^-(2^-1 i3pi))/(2i) = -1 if you could show me this that would be really great btw e is eulers number i = imaginary number sqrt -1 and pi = 3.14... THANKS!!!

*June 11, 2010*

**Algebra 2**

a rectangle table is five times as long as it is wide if the area is 245 feet ^2 find the length and width of the table

*June 7, 2010*

**chemistry**

How much Fe++ could be present in water containing 0.8 x 1e-02 M HCO3- (bicarbonate) without causing the precipitation of FeCO3 (Ksp=10**(-10.7))

*June 4, 2010*

**Chemistry**

nevermind..i got it

*May 26, 2010*

**Chemistry**

Magnesium fluoride dissolves in water to the extent of 8.0 10-2 g/L at 25°C. Calculate the solubility of MgF2(s) in moles per liter, and calculate Ksp for MgF2 at 25°C. I've been doing this and getting .086. Please help!

*May 26, 2010*

**Algebra**

Write an equation of the line satisfyingg the given conditions. Slope = -2/3; y-intercept of 2

*May 23, 2010*

**Math (trig)**

4cos(x)+5=6sec(x)

*May 20, 2010*

**Algebra**

Determine whether the lines are parallel, perpendicular, or neither. y = 9x + 9 and y = -9x + 9

*May 16, 2010*

**Algebra**

Write an equation of the line satisfying the given conditions. Horizontal line through (-2, -5)

*May 16, 2010*

**Math**

Thanks, I am so lost.

*May 16, 2010*

**biology**

Pick one of the multiple choice that best matches the answer. For grasshoppers and locusts to be in the same family they must also be in the same a. order b. group c. genus d. species two members of the same ___ would be most clostly related. a. order b. group c. genus d. species

*May 13, 2010*

**spanish**

what is the conjugation for I listened He use to take I slept

*May 12, 2010*

**Economics**

Programs aimed only at people who are poor or disabled are known as? a. social insurance programs b. governmental programs c. federally funded programs d. public assistance programs

*May 10, 2010*

**PreCalculus REINY HELP PLEASE**

well yay thanks for the answer but i really need the formula lol I tried to derive it on my own but it was a little bit rough lol i need the formula it wasn't in my book and I don't know what the name of the formula would be so i can't really google it...

*April 28, 2010*

**PreCalculus**

Hi im unsure how do this problem becasue I do not how to go about these types of problems were you make monthely payments each month of the same amount... Janene contributes $50 per month inot the Chaing China Bond Fund htat earns 7.26% annual intrerest. What is the value of ...

*April 28, 2010*

**Precalculus**

Hi im unsure how do this problem becasue I do not how to go about these types of problems were you make monthely payments each month of the same amount... Janene contributes $50 per month inot the Chaing China Bond Fund htat earns 7.26% annual intrerest. What is the value of ...

*April 28, 2010*

**PreCalculus**

Still need help please post in this one that way i don't have to search through the old stuff h t t p : / / w w w . j i s k h a . c o m / d i s p l a y . c g i ? i d = 1 2 7 2 3 2 6 8 8 0

*April 27, 2010*

**Precalculus**

please still stuck h t t p : / / w w w . j i s k h a . c o m / d i s p l a y . c g i ? i d = 1 2 7 2 3 2 6 8 8 0

*April 26, 2010*

**PreCalculus**

Hi i don't know how to do this problem solve for n^3 given that log(40 SQRT(3))/log(4n) = log(45)/log(3n) Thanks i'm copletely lost and don't know how to solve

*April 26, 2010*

**PreCalculus**

question skipped again please post response in this one so that way I don't have to search for old posts h t t p : / / w w w . j i s k h a . c o m / d i s p l a y . c g i ? i d = 1 2 7 2 2 4 7 5 4 8

*April 26, 2010*

**Precalculus**

please post response in this forum so i don't have to search for the old one u skipped this question still need help h t t p : / / w w w . j i s k h a . c o m / d i s p l a y . c g i ? i d = 1 2 7 2 2 4 0 9 7 0

*April 25, 2010*

**PreCalculus**

Hi im unsure how do this problem becasue I do not how to go about these types of problems were you make monthely payments each month of the same amount... Janene contributes $50 per month inot the Chaing China Bond Fund htat earns 7.26% annual intrerest. What is the value of ...

*April 25, 2010*

**human resources**

How can a technology manager help their company to grow?

*April 7, 2010*

**chemistry**

How do you find out how many moles of water were produced in this reaction?

*April 6, 2010*

**chemistry**

How many moles of acid were present in 50 ml or 1.0M HCl? How many moles of water were produced in this reaction?

*April 6, 2010*

**mathematics in our world**

how often do you run red lights

*April 4, 2010*

**math**

surface area of a rectangular prisms i have one with the same # on each side how many times should i * it

*March 31, 2010*

**band**

i play the clarinet i was just wondering if anyone knew any good website to practice

*March 31, 2010*

**band**

can you give some music leaning site

*March 31, 2010*

**Probability/Stas**

does that mean sixty of them

*March 31, 2010*

**Probability/Stas**

10 20

*March 31, 2010*

**math**

i have to find the suface area of rectangular prisms here is the problem 9*2.1 2.1*4.4 4.4*9 i got 135.48 is that right

*March 31, 2010*

**4th grade math**

4x27

*March 30, 2010*

**Spanish**

El Laberinto del Fauno Guillermo del Toro Escribe 3 -4 frases para cada pregunta. Responde a dos preguntas en español, y a dos preguntas en inglés. i need help answering these questions in spanish? 1) ¿Están enamorados el capitán y la madre ...

*March 30, 2010*

**Precalc**

I think it was skiped can you post resposne in this question h t t p : / / w w w . j i s k h a . c o m / d i s p l a y . c g i ? i d = 1 2 6 9 8 2 9 1 7 1

*March 28, 2010*

**PreCalc**

[b]1. The problem statement, all variables and given/known data[/b] The average growth rate of the population of a certain city is 7.5% per year. The city's population is now 22,750 people. What is the expected population in 10 years? [b]2. Relevant equations[/b] I was ...

*March 28, 2010*

**axia**

how do social dominance and courtship diplays have an impact on evolution

*March 24, 2010*

**social studies**

6th grade question:what were greek city-states and how did they function

*March 24, 2010*

**japanese**

How would you say: next month on April 14th I am going with my parents on vacation to Hawaii. In katakana and hirgana only please.

*March 20, 2010*

**Math-Rational #'s**

Just trying to understand this. Please let me know if I did these right. Thanks!!! -7 as a rational # = -7/10 -3.03 as a rational # = -33/10 -2 3/12 as a rational # = -25/12 1.03 as a rational # = 13/10

*March 15, 2010*

**Chemistry**

8 h2o

*March 10, 2010*

**Statistics**

A die that is fair will have each face of the die come up one-sixth of the time in the long run. The population for die throwing contains the results of throwing the die an infinite number of times. For this problem, the parameter of interest is p is the probability of rolling...

*March 9, 2010*

**Statistics**

A student group claims that first-year students at a university must study 2.5 hours (150 minutes) per night during the school week. A skeptic suspects that they study less than that on the average. A class survey finds that the average study time claimed by 269 students is = ...

*March 9, 2010*

**Physics**

A person walks 24.0° north of east for 2.80 km. How far would another person walk due north and due east to arrive at the same location?

*March 9, 2010*

**PreCalculus**

I'm unsure how to even start this problem Solve for x: Arctan( -4/5 ) + Arcos (2/SQRT(5) ) = Arctan(x)

*March 9, 2010*

**college english**

that's helps a whole lot! thanks so much Ms Sue and Writeacher! :D

*March 7, 2010*

**college english**

In the essay, I have to demonstrate that I recognize logical fallacies, but I don't understand how I can write that much about a message of somebody else when they have written so little. there's just nothing else to speak of, and I only have 500 words

*March 7, 2010*

**college english**

what do you mean by newspaper's op ed page?

*March 7, 2010*

**college english**

I was told in class to find a piece of "biased writing" and use the knowledge about critical thinking. how would i know whether an article is biased? really confused. also, it's a 1000 word essay, so it'd be really nice to get answer!

*March 7, 2010*

**Physics (Heat Engines)**

wait no the answer is A how though?

*March 6, 2010*

**Physics (Heat Engines)**

21. A heat engine operates in a cycle between temperatures 700 K and 400 K. The heat input to the engine during each cycle is 2800 J. What is the maximum possible work done by the engine in each cycle? (A) 1200 J (B) 1600 J (C) 2100 J (D) 2800 J (E) 4400 J I believe that the ...

*March 6, 2010*

**Math**

yes, it does! Thank you!

*March 3, 2010*

**Math**

zero

*March 3, 2010*

**Math**

suppose the temperature is -12 degrees F and rises 4 degrees every hour for 3 hours. What will the temp b then? Can you please help me write out the equation? Thanks

*March 3, 2010*

**pre calc**

A ramp leading to a freeway overpass is 470 feet long and rises 32 feet. What is the angle of inclination of the ramp?

*March 3, 2010*

**Physics 103**

How do I start? Problem: A helium nucleus (m= 6.65 x 10^-27 kg and q = 2e)is initially at rest. It is accelerated through a potential difference delta V and then enters a region with a constant magnetic field of strength B= 4T. It enter perpendicular to the field and undergoes...

*March 2, 2010*

**Physics 103**

So I have a question about magnetism. A charged particle moves through a region of space and experiences no magnetic force. Does that mean that the magnetic field is zero?

*March 2, 2010*

**math**

i have the capacity of 1 literbut all the water in the ocean can not fill me up.what am i?

*March 2, 2010*

**Chemistry**

Bromine can be added to limonene to create a brominated compound. When 613 mg of limonene and 3.5 mL of a 10% (v/v) solution of Br2 in dichloromethane (a solvent) are combined, 959 mg of the product is isolated. Calculate the percent yield for this reaction. If the limonene ...

*March 2, 2010*

**Physics**

h t t p : / / i m g 7 1 5 . i m a g e s h a c k . u s / i m g 7 1 5 / 2 7 6 9 / c a p t u r e q u . j p g I need help with c. for a. I got v = sqrt(2gR) for b. I got v = sqrt(gR) for c. I'm stuck

*March 1, 2010*

**RESPONSE to PreCalc**

I like how Jishka adds random symbols to my posts lol awsome :O

*March 1, 2010*

**RESPONSE to PreCalc**

Makes complete sense thank you so much!!! My only question is how come we respect domains only sometimes... For example now sin©¬/cos©¬ = (1/a)/(¡î3/a) = 1/¡î3 tan©¬ = 1/¡î3 ©¬ = 30¨¬ or pi/6 then ...

*March 1, 2010*

**Precalculs**

I have no idea how to do these type of problems. -------Problem-------- Solve each equation on the interval 0 less than or equal to theta less than 2 pi 42. SQRT(3) sin theta + cos theta = 1 ---------------------- There is an example prior to the excersises that attempts to ...

*February 28, 2010*

**Physics**

h t t p : / / i m g 2 0 5 . i m a g e s h a c k . u s / i / c a p t u r e b b . j p g / i am stuck on part c how do i find work with out using the spring constant work equals force parallel times displacement at which the force is acted during... Work done by spring = .5 kx^2 ...

*February 28, 2010*

**Math--Exponential Functions**

Suppose an investment of $500 doubles in value every 15 years. How much is the investment worth after 30 years? After 45 years? please help!!! i don't even understand how to approach this problem! =(

*February 28, 2010*

**Physics**

hmmmmmm thanks

*February 28, 2010*

**Physics**

h t t p : / / w w w . j i s k h a . c o m / d i s p l a y . c g i ? i d = 1 2 6 7 3 9 3 5 9 3 ok heres the problem in a picture h t t p : / / i m g 1 9 2 . i m a g e s h a c k . u s / i m g 1 9 2 / 4 5 0 0 / c a p t u r e x x w . j p g ok I called the 4 kg block m3 and the 2 ...

*February 28, 2010*

**Physics**

wait no 12 N

*February 28, 2010*

**Physics**

Is C just 9.8 N

*February 28, 2010*

**Physics**

Three blocks of masses 1.0, 2.0, and 4.0 kilograms are connected by massless strings, one of which passes over a frictionless pulley of negligible mass, as shown above. Calculate each of the following. a. The acceleration of the 4 kilogram block b. The tension in the string ...

*February 28, 2010*

**physics help**

is it no damping for all of them

*February 27, 2010*

**physics help**

f(x)=squareroot5cos1.2x f(x)=xsin4x f(x)=x^3sin5x

*February 27, 2010*

**physics help**

Damped Oscillations 1. (a) For each of following graphs, determine if graph shows damped oscillation. (b) if it shows damped oscillation : (i) identify damping factor (ii)where damping occurs Note : use a graphing calculator to sketch these graphs f(x) = ¡î5 cos 1....

*February 27, 2010*

**5th grade**

that is languages arts

*February 24, 2010*

**reading/science**

i really suck at spelling

*February 24, 2010*

**reading/science**

we have to readsearch in the plants i have the the plant uranus and i'm wondering if you can give me some websites

*February 24, 2010*

**social studies**

is it new brunswick,quebec,prince edward island,and ladrodor and thank you ms.sue

*February 22, 2010*

**social studies**

the great plains of canada are found in the canada provinces of

*February 22, 2010*

**social studies**

the appalachian mountain extend north from the united states into the canadian provinces of ______,______ ______,______ _____ _____,and _______

*February 22, 2010*

**Earth Science**

Upon what measurement is the Earth's latitude and longitude system based?

*February 18, 2010*

**pre calc need help**

A square is drawn inside a square. Find the area of the square as a function of the radius of the circle

*February 17, 2010*

**ALGEBRA**

the value, v, of a shopkeeper's inventory software program is given by v = 1/2t + 6, where t is the number of years since the shopkeeper bought the program. What is the program worth 4 years after it is first purchased? Plot the point with the given t-value, 4

*February 16, 2010*

**Biology**

why did the nuclei enriched fraction appear in the centrifuge fraction spun at the slower speed? Why didn't this fraction contain only nuclei(Why wasn't it pure?)?

*February 11, 2010*