Tuesday

June 28, 2016
Total # Posts: 789

**Chemistry: Check my answers please!**

How would each of the following affect the Cr(VI) concentration determined in this experiment? Justify the answers with an explanation. In the experiment, absorption spectroscopy was used to obtain the concentration of Cr(VI) ions. 1) A student adds more standard solution than...
*March 2, 2014*

**Chem**

How would one be able to identify the lambda max of Cr(III) at a concentration less than 70ppm from a graph? I couldn't post the graph, but I don't understand how one would be able to do this? Can you please justify the answer with an explanation? I would want to know ...
*March 2, 2014*

**Chemistry**

How would one be able to identify the lambda max of Cr(III) at a concentration less than 70ppm from a graph? I couldn't post the graph, but I don't understand how one would be able to do this? The graph had the Chromium Absorbance Spectra of 70ppm for Cr(VI) and Cr(III...
*March 2, 2014*

**Chemistry**

How would one be able to identify the lambda max of Cr(III) at a concentration less than 70ppm from a graph? I couldn't post the graph, but I don't understand how one would be able to do this? The graph had the Chromium Absorbance Spectra of 70ppm for Cr(VI) and Cr(III...
*March 2, 2014*

**Chemistry**

How would each of the following affect the Cr(VI) concentration determined in this experiment? Justify the answers with an explanation. In the experiment, absorption spectroscopy was used to obtain the concentration of Cr(VI) ions. 1) A student adds more standard solution than...
*March 2, 2014*

**chemistry**

1) List a series of tests that would determine the order of activity (least active to most active) for Zn, Mn, and Ag. 2) What would be the reaction for the addition of excess OH- ions to Mg(NO3)2 and Cu(NO3)2? This is a complex ion forming reaction. Would the complete ionic ...
*March 2, 2014*

**Chemistry**

Why is a blank solution used in absorption spectroscopy? I know it is to nullify the reflection, refraction, and diffraction that occurs, but if the blank solution was a dilute solution rather deionized water, how would the concentration of Cr(VI)in a sample be affected?
*February 25, 2014*

**Chemistry**

In an emission spectroscopy, when trying to identify the most intense emission line for an ion, does one have to identify it using the wavelength and the intensity?
*February 23, 2014*

**Chemistry**

In this experiment absorption spectroscopy is conducted to detect Cr(VI)in aqueous solutions and with it the concentration of Cr(VI). How would each of the following affect the Cr(VI) concentration determined in this experiment? Explain the answer. 1. A student adds more ...
*February 23, 2014*

**Math**

Find the LCM of: 72 and 99 72 and 54
*February 22, 2014*

**chemistry**

What is the mass of a sample of ammonia that contains 0.750 moles of hydrogen atoms? The answer is 4.26g, but I do not know how to set up the equation.
*February 22, 2014*

**Math**

No. I need help
*February 19, 2014*

**Math**

Three pigs and two piglets weigh 32 kg. Four pigs and five piglets weigh 59 kg. What is the weigh of one pig and one piglet? A) 13 kg B) 91 kg C) 7 kg D) none of these
*February 19, 2014*

**Chemistry**

1. A student uses 6M HCl solution contaminated with Al(NO3)3 to wash the nichrome wire in between recordings of emission spectra for the different known and unknown metal ion solutions. The emission energies for the aluminum are 3.90x10^-19 J/atom, 3.58x10^-19 J/atom, and 2....
*February 16, 2014*

**Math **

Mr.Fox's fourth grade class of 20 students had an average of 72% on their last test. However, Rose's mark of 76% had been incorrectly recorded as 56 %. What was the correct class average for the test? A) 82% B) 80% C)73% D) 62%
*February 16, 2014*

**Math**

Find the lowest common multiple for 16 and 20
*February 16, 2014*

**trigonometry**

If a tree casts a shadow of 12 feet at the same time that 6 foot person casts a shadow what is the length of the three to the nearst foot
*February 8, 2014*

**Calculus**

A steady wind blows a kite due west. The kite's height above ground from horizontal position x = 0 to x = 60 ft is given by the following. y= 155-(1/40)(x-50)^2 Find the distance traveled by the kite.
*February 4, 2014*

**Calculus**

Find the distance traveled by the kite
*February 4, 2014*

**Calculus**

A steady wind blows a kite due west. The kite's height above ground from horizontal position x = 0 to x = 60 ft is given by the following. y= 155-(1/40)(x-50)^2
*February 4, 2014*

**Calculus**

Use Simpson's Rule with n = 10 to estimate the arc length of the curve. y = tan x, 0 < x < π/9
*February 4, 2014*

**MATH**

OK, Thanks!
*February 4, 2014*

**MATH**

Select the measure of the complement or supplement of the angle. If there is no complement or supplement, select no complement or supplement. 55.1° 124.9° 119.9° 49.9° no complement or supplement
*February 4, 2014*

**English ~CHECK MY WORK PLEASE~**

*Please Note: the the answer with stars next to them are my answers. 1. Imagine you have been asked to read another article about gymnasts. It has the following title and subheads: Title: Gymnasts: For the Love of the Sport Subhead #1: The Naysayers Subhead #2: Lasting ...
*February 4, 2014*

**Art ~ Goya & His Painting **

What message was goya trying to send when he painted the family of King Carlos IV?
*February 3, 2014*

**chemistry**

The laboratory tech accidentally mixed NaHCO3 with BaCl2-2H2O instead of KCl when preparing unknown mixture for this experiment. How would this mistake affect the calculated percentage of NaHCO3 in the mixture? Justify answer with an explanation. Is it still possible to ...
*February 2, 2014*

**chemistry**

A student dried a wet crucible with a Kimwipe. A piece of Kimwipe was left clinging to the inside wall of the crucible, The student did not see the piece of Kimwipe when adding the NaHCO3-KCl mixture to the crucible. The crucible ans its contents were weighed and subjected to ...
*February 2, 2014*

**Chemistry**

A student cleaned a crucible with HCl. After pouring the HCl into the waste container, the crucible was neither rinsed with water or dried before the student added the NaHCO3 and KCl mixture. The crucible contained some residual HCl. How would this experimental error affect ...
*February 2, 2014*

**Art ~ Goya & His Painting **

What message was Goya trying to send when he painted Charles the IV and his family?
*January 31, 2014*

**Science ~ Structures and Properties of Matter**

SO Sorry !
*January 28, 2014*

** Science ~ Structures and Properties of Matter**

1) Both carbon dioxide and water are pure substances. How are they similar to each other? A. both substances have a set ratio of atoms that cannot be separated by physical means. B. both substances have a set ratio of atoms that can be separated by physical means. C. both ...
*January 28, 2014*

**science ~CHECK MY WORK PLEASE~**

So Sorry!!!
*January 28, 2014*

**Science ~CHECK MY WORK PLEASE~**

SO SORRY!
*January 28, 2014*

**Calculus**

The figure shows graphs of the marginal revenue function R ' and the marginal cost function C ' for a manufacturer. (Recall from Section 4.7 that R(x) and C(x) represent the revenue and cost when x units are manufactured. Assume that R and C are measured in thousands ...
*January 25, 2014*

**Calculus**

a)Find the number a such that the line x = a bisects the area under the curve y= 1/x^2, 1<x<3. a=3/2 b)Find the number b such that the line y = b bisects the area in part (a) b=?
*January 25, 2014*

**Calculus**

Sketch the region and find its area. S = {(x,y) | x > -6, 0 < y < e-x/2}
*January 25, 2014*

**Math**

32. The area of a square postage stamp is 81/100 in. to the second power. What is the side length of the stamp? 33. The area of a square boxing ring is 484 ft. to the second power. What is the perimeter of the boxing ring?
*January 23, 2014*

**physics**

A tennis ball has a mass of 0.057 kg. A professional tennis player hits the ball hard enough to give it a speed of 52 m/s (about 117 miles per hour.) The ball moves toward the left, hits a wall and bounces straight back to the right with almost the same speed (52 m/s). As ...
*January 23, 2014*

**physics**

A 0.55 kg block of ice is sliding by you on a very slippery floor at 4 m/s. As it goes by, you give it a kick perpendicular to its path. Your foot is in contact with the ice block for 0.0025 seconds. The block eventually slides at an angle of 23 degrees from its original ...
*January 23, 2014*

**algebra**

How much of the 50% and 80% solutions does the teacher have?
*January 17, 2014*

**Physics**

Okay, I figured out the volume, I just need help finding the tension. What should I do to find that?
*January 17, 2014*

**Physics **

I'm super confused about how to approach this problem. Please help. A ball of Styrofoam (ρ = 100 kg/m3) is totally submerged in water. The ball has a mass of 300.0 g What is the volume of the ball? If a string holds the ball when it’s in the water, what’s ...
*January 17, 2014*

**math**

p= 20x where p is equal to the number of pens, and x is equal to the number of boxes that Sheila has purchased.
*January 17, 2014*

**math**

There isn't a table in Part A. This means that if Diana practices for 3 hours she will win 10 tennis matches. Part B = 10 And for Part C just plug in a number for b and put it in place for x. For example if she practiced for 2 hours the equation would look like this 3(2)+1...
*January 17, 2014*

**math**

A, because all sides of a square are the same length. If the width of the square is 3 then the length will be 3. LxW=area 3x3=9 so it's A.
*January 17, 2014*

**physics**

A spring of stiffness 127 N/m, and with relaxed length 0.19 m, stands vertically on a table, as shown in the figure. Instead of compressing the spring with a heavy block, with your hand you push straight down on the spring until your hand is only 0.14 m above the table. (...
*January 17, 2014*

**World Geograpy**

1. Which of the following were the main proponents of NAFTA? A. Environmentalists B. Human rights groups C. Labor unions D. Large corporations 2. Which of the following is the primary subsistence crop in Latin America? A. Potatoes B. Beans C. Corn D. Wheat 3. Among the ...
*January 2, 2014*

**World Geograpy**

1. With respect to global connections, association with _______ offers the brightest immediate future for many African countries. A. India B. the European Union. C. China D. the United States. 2. Slum areas called shantytowns occur in _________ major African cities, housing ...
*January 2, 2014*

**World Geograpy **

1. With regard to British influences on India, which of the following statements is true? A. The common name for the British Indian Empire was the "British Raj." B. The British East India Company ruled India after a sepoy rebellion in 1867. C. The British Indian Army...
*January 2, 2014*

**chem**

7.75 litres of radon gas is at 1.55 atm and -19 degrees c what is the volume at stp
*December 10, 2013*

**Language Arts**

What did Thura’s family and Zdenko’s parents choose to do when they were faced with overwhelming conflicts?
*December 9, 2013*

**Math**

thank you
*December 3, 2013*

**Math**

the diameter of the pizza was 14 inches. What was the ratio of the radius to the diameter of the pizza?
*December 3, 2013*

**Principles of Finance **

.A thirty year US treasury bond has a 4.0 percent interest rate.In contrast, a ten year Treasury bond has an interest rate of 2.5 percent. A maturity risk premium is estimated to be 0.2 percentage points for the longer maturity bond. Investors expect inflation to average 1.5 ...
*November 12, 2013*

**Math**

Thank you again and have a good night!
*November 11, 2013*

**Math**

Also 25x7=175
*November 11, 2013*

**Math**

24x10=240
*November 11, 2013*

**Math**

Estimate using compatible numbers 24x8
*November 11, 2013*

**Math**

Thank you!
*November 11, 2013*

**Math**

Estimate using compatible numbers 611÷14
*November 11, 2013*

**Math**

I am confused. Estimate using compatible numbers 611÷14 and 76+8
*November 11, 2013*

**Math**

Thank You! Ms. Sue & Sam :)
*November 7, 2013*

**Math**

Sorry for # 3 is like this : 3) 22miles/55 hours = 12miles/h hours 48 30 ************* 45 22
*November 7, 2013*

**Math**

Please Check My Answer I don't know if they are right or wrong and if they are wrong can u give me the correct answers. ? Thanks PS: The answers are the * one's. 1) 2/3 = 12/x x= 18 x= 12 x= 36 x= 8 **************** 2) 6/11 = 84/x x= 40 ************** x= 120 x= 254 x= ...
*November 7, 2013*

**physics**

A car of mass 1420 kg rests on a hydraulic lift with a piston of radius 0.26 m that is connected to a second piston of radius 0.032 m. If the car is just barely lifted off the ground, what is the force at the second piston?
*November 3, 2013*

**Math**

Thank you
*October 27, 2013*

**Math**

An analog clock can serve as a visual reference for twelfths. At 1 o'clock the hands mark off 1/12 of a circle at 2 o'clock the hands mark off 2/12 of a circle and so on. How many twelfths are in each of these fractions of a circle? 1/2, 1/4, 1/3, 1/6
*October 27, 2013*

**Math**

an analog clock can serve as a visual Reference for twelfths. at 1 o clock the hands mark off 1/12 of a circle at 2 o clock the hands mark off 2/12 of a circle and so on. how many twelfths are in each of these fractions of a circle? 1/2, 1/4, 1/3, 1/6
*October 27, 2013*

**Math**

Thank you
*October 27, 2013*

**Math**

Form 1 1/2 circles using only 1/4s. How many 1/4 pieces are needed to make 1 1/2?
*October 27, 2013*

**Chemistry**

1. A student uses 6M HCl solution contaminated with Al(NO3)3 to wash the nichrome wire in between recordings of emission spectra for the different known and unknown metal ion solutions. The emission energies for the aluminum are 3.90x10^-19 J/atom, 3.58x10^-19 J/atom, and 2....
*October 14, 2013*

**Math**

Thank you
*October 14, 2013*

**Math**

I am confused with rule of pattern 1,3,6, I figured out 10 is the next number Rule: find the difference and add 1 to the next item
*October 14, 2013*

**Math**

State the rule for this pattern: 1,5,11,19 What about: subtract the last number and add 2 to the next term
*October 14, 2013*

**math**

Is this correct:find the difference and add 2 to the next term
*October 14, 2013*

**Math**

What about subtract the last number and add 2 to the next term
*October 14, 2013*

**Math**

State the rule for this pattern: 1,5,11,19 I want to make sure this is correct add the last number from before and 2 more
*October 14, 2013*

**social studies**

Thank you
*October 8, 2013*

**social studies**

The rise was the fertile land the fall was the civilization becoming overpopulated.
*October 8, 2013*

**social studies**

What patterns do you see in the rise and the fall of many civilization in the Fertile Crescent?
*October 8, 2013*

**Math**

692-405=287 miles
*October 6, 2013*

**Math**

It is 405 miles from Minneapolis, Minnesota to Chicago, Illinois. It is 692 miles from Minneapolis to Cincinnati, Ohio. Cincinnati is how many miles farther from Minneapolis than Chicago? Write an equation and solve the problem
*October 6, 2013*

**Psychology**

1. A company decides to add a new program that prepares randomly selected sales personnel to increase their number of sales per month. The mean number of sales per month for the overall population of sales people at this national company is 25 with a standard deviation of 4. ...
*October 5, 2013*

**physics**

You are pushing a refrigerator across the floor of your kitchen. You exert a horizontal force of 294 N for 7.6 s, during which time the refrigerator moves a distance of 3.2 m at constant velocity. (a) What is the total work (by all forces) done on the refrigerator? (b) What is...
*September 30, 2013*

**Computer Science**

I need help with this problem. I don't know how to set it up correctly. Input a list of positive numbers (terminated by 0)into an array, and output the result. Use a subprogram to output the numbers, a function to find the mean, an a subprogram to output the result. I know...
*September 28, 2013*

**humanservices101**

Critical thinking question: how is current child welfare policy and practice shaped by religious and philosophical beliefs, societal structures, and economic systems?
*September 27, 2013*

**English**

Please evaluate the writing, grammar, style, spelling as well as content. People take out oil from the sands in AB so we can drive and leave tailings ponds. This caused a lot of damage to the land and negative impacts to wildlife. Natives get sick from eating to many fish from...
*September 21, 2013*

**Accounting**

Why is it more difficult to account for the inventory of a manufacturing firm than for that of a merchandising firm?
*September 18, 2013*

**Algebra**

Find the average speed Hike 52 miles in 3 days Drive 69 kilometers in 3/4 hour
*September 15, 2013*

**public speaking**

when using the internet to conduct research,it is most important to?
*September 11, 2013*

**social studies; same study diff question**

which one of the following conclusions is supported by the results of these studies? 1)characteristics other than one's name have no effect on academic achievement. 2)Unusual names do not determine intellectual development. 3)Ethnic group membership is the main factor ...
*September 8, 2013*

**Math**

Is this a trick question? I need to write the number 79 in short word form, would it be seventy 10's and one 9 or 10 sevens and 9 ones? Please, please, please help me Thank You
*September 4, 2013*

**Math**

Would 72,060,964,765 look like the following in it's expanded form? 7X 10,000,000,000 + 2X 1,000,000,000 + 0X 100,000,000 + 6X 10,000,000 + 0X 1,000,000 + 9X 100,000 + 6X 10,000 + 4X 1,000 + 7X 100 + 6X 10 + 5X 1 been working on this for 1 hour!
*September 3, 2013*

**Physics**

A car driving at 14m/s hits the brakes and comes to a stop in 4.1 seconds. What was the car's acceleration during this stop?
*August 18, 2013*

**History**

I have a paper I must do and have been trying all summer to finish. I have read the book The Story of Sacagawea and now what I need to do is write what the main idea/topic is ( which I know is Sacagawea) but then I have to write a main idea's # 1 and # 2 and details to ...
*August 15, 2013*

**Reading**

Can you please write this into terms easier to understand? Thanks! Private life was infected with impurity to which licentiousness of the Catholic clergy appeared like innocence.
*August 11, 2013*

**Reading**

Oh. Ok. Makes sense. Thanks!
*August 10, 2013*

**Reading**

Can you please rewrite this sentence into terms easier to understand? Thanks. Now celibacy yielded to widespread clerical concubinage and, in the convents, to promiscuity.
*August 10, 2013*

**algebra1 HELP PLEASE Thanks you!!**

Two identical rubber balls are dropped from different heights. Ball 1 is dropped from a height of 100 feet, and ball 2 is dropped from a height of 210 feet. Write a function for the height of each ball. h1(t) = h2(t) = When does ball 1 reach the ground? Round to the nearest ...
*July 8, 2013*