Monday

July 25, 2016
Number of results: 51,078

**math help**

Use the following table to answer the questions. (Give your answers correct to two decimal places.) x 1 1 3 3 5 5 7 7 9 9 y 3 2 6 1 3 3 3 2 5 3 (a) Find the equation of the line of best fit. y hat = + x (ii) Graph this equation on a scatter diagram. (Do this on paper. Your ...
*June 26, 2013 by Tracy *

**Rate Constant - My Work is Incorrect**

Hi! I am stuck with this question and I would like to know what I did wrong: Given that the initial rate constant is 0.0160 s-1 at an initial temperature of 25 degrees C, what would the rate constant be at a temperature of 130 degrees C for the same reaction described in Part ...
*February 3, 2013 by Amy*

**Calculus**

y = f(x) = x^2 - 3 x (a) Find the average rate of change of y with respect to x in the following intervals. from x = 2 to x = 3 Incorrect: Your answer is incorrect. from x = 2 to x = 2.5 Incorrect: Your answer is incorrect. from x = 2 to x = 2.1 Incorrect: Your answer is ...
*February 5, 2016 by Anonymous*

**math**

Can someone please help me on these I have look at the examples and done just what they did, but I still get it wrong and I only have one more time to try. Use the following table to answer the questions. (Give your answers correct to two decimal places.) x 1 1 3 3 5 5 7 7 9 9...
*June 23, 2013 by tracy12*

**Math**

Does studying for an exam pay off? The number of hours studied, x, is compared with the exam grade received, y. x 7 7 5 5 7 y 95 90 75 85 95 (a) Complete the preliminary calculations: SS(x), SS(y), and SS(xy). Incorrect: Your answer is incorrect. . (SS(x)) (my answer was 100.9...
*May 29, 2013 by DeeDee*

**physics6**

In a cathode ray tube, electrons are accelerated from rest by a constant electric force of magnitude 6.2 multiplied by 10-17 N during the first 2.2 cm of the tube's length; then they move at essentially constant velocity another 43 cm before hitting the screen. (a) Find the ...
*February 16, 2012 by Anonymous*

**physics14**

In a cathode ray tube, electrons are accelerated from rest by a constant electric force of magnitude 6.2 multiplied by 10-17 N during the first 2.2 cm of the tube's length; then they move at essentially constant velocity another 43 cm before hitting the screen. (a) Find the ...
*February 16, 2012 by jm*

**statistics**

Use the following table to answer the questions. (Give your answers correct to two decimal places.) x 1 1 3 3 5 5 7 7 9 9 y 3 1 3 1 6 3 6 1 4 4 (a) Find the equation of the line of best fit. y hat = + x (ii) Graph this equation on a scatter diagram. (Do this on paper. Your ...
*November 1, 2013 by statistics student*

**Elementary Satistics**

Test the following function to determine whether it is a probability function. If it is not, then make it into a probability function. (Give your answers correct to one decimal place.) R(x) = 0.2, for x = 0, 1, 2, 3, 4 (a) List the distribution of probabilities. R(0) =0 ...
*September 21, 2014 by Vickie Huff*

**Chemistry **

Your Open Question Show me another » Chemistry help needed... Confused? The following reaction is first order and the rate constant is 2.35 x 10^-4 s^-1 at 20 degress C. 2 N2O5 -----> 2 N2O4 + O2 A.) What is the rate of reaction if the [N2O5]=.25 M? B. What would the [N2O5...
*November 20, 2012 by Krissy *

**physics**

Vector V1 is 8.58 units long and points along the -x axis. Vector V2 is 4.45 units long and points at +40.0° to the +x axis. (a) What are the x and y components of each vector? V1x = Incorrect: Your answer is incorrect. V1y = Incorrect: Your answer is incorrect. V2x = ...
*September 25, 2012 by royaa*

**calculus**

Maximize p = 2x + 2y subject to 4x + 8y 24 8x + 4y 32 x 0 , y 0 (Round all answers to the nearest 0.1.) p = Incorrect: Your answer is incorrect. x = Incorrect: Your answer is incorrect. y = Incorrect: Your answer is incorrect.
*November 13, 2011 by LC*

**Chemistry **

A student tested the effect of temperature on the decomposition of N2O5. He found that the rate of the reaction at a lower temperature was 4.2 x 10–3 s–1 and the rate at a higher temperature was 1.6 x 101 s–1. What is wrong with the student's data? A. Nothing. Rate constants ...
*March 25, 2015 by Cortney*

**ALGEBRA**

If the principal P = $500, the rate r = 5 1 2 %, and time t = 1 year, find the following. (a) What is the amount of interest? $ Incorrect: Your answer is incorrect. (b) What is the future value?
*April 25, 2012 by Randy*

**math**

Consider the following bivariate data. Point A B C D E F G H I J x 3 4 2 1 7 2 1 0 4 2 y 1 7 3 3 6 6 5 0 6 2 (a) Construct a scatter diagram of the given bivariate data. (Do this on paper. Your instructor may ask you to turn in this work.) (b) Calculate the covariance. (Give ...
*June 25, 2013 by tracy12*

**Physics**

A 5.50-kg ball, moving to the right at a velocity of +2.35 m/s on a frictionless table, collides head-on with a stationary 7.60-kg ball. Find the final velocities of the balls if the collision meet the following conditions. (a) elastic 5.5-kg ball = Incorrect: Your answer is ...
*March 26, 2013 by Anonymous*

**statistics**

Does studying for an exam pay off? The number of hours studied, x, is compared with the exam grade received, y. x 7 7 5 5 7 y 95 90 75 85 95 (a) Complete the preliminary calculations: SS(x), SS(y), and SS(xy). Incorrect: Your answer is incorrect. . (SS(x)) Incorrect: Your ...
*May 26, 2013 by Tom*

**Statistics**

Does studying for an exam pay off? The number of hours studied, x, is compared with the exam grade received, y. x 7 7 5 5 7 y 95 90 75 85 95 (a) Complete the preliminary calculations: SS(x), SS(y), and SS(xy). Incorrect: Your answer is incorrect. . (SS(x)) Incorrect: Your ...
*May 26, 2013 by Tom*

**physics**

The speed of a point on a rotating turntable, which is 0.264 m from the center, changes at a constant rate from rest to 0.902 m/s in 1.94 s. At t1 = 0.64 s, find the magnitude of the tangential acceleration. Answer in units of m/s2 I assumed the velocity was constant so i ...
*September 9, 2011 by squires*

**physics**

The speed of a point on a rotating turntable, which is 0.264 m from the center, changes at a constant rate from rest to 0.902 m/s in 1.94 s. At t1 = 0.64 s, find the magnitude of the tangential acceleration. Answer in units of m/s2 I assumed the velocity was constant so i ...
*September 10, 2011 by squires*

**physics**

The speed of a point on a rotating turntable, which is 0.264 m from the center, changes at a constant rate from rest to 0.902 m/s in 1.94 s. At t1 = 0.64 s, find the magnitude of the tangential acceleration. Answer in units of m/s2 I assumed the velocity was constant so i ...
*September 12, 2011 by squires*

**physics**

The speed of a point on a rotating turntable, which is 0.264 m from the center, changes at a constant rate from rest to 0.902 m/s in 1.94 s. At t1 = 0.64 s, find the magnitude of the tangential acceleration. Answer in units of m/s2 I assumed the velocity was constant so i ...
*September 12, 2011 by squires*

**chemistry**

A certain first order reaction has a rate constant of 5.68 x 10–3 s–1 at 139°C and a rate constant of 8.99 x 10–1 s–1 at a temperature of 215°C. Ea = 111 kJ mol– q1) What is the value of the rate constant at 275°C? q2) At what temperature does the rate constant have a value of...
*June 2, 2016 by jane *

**physics**

A 5.3-kg block is pushed 2.3 m up a vertical wall with constant speed by a constant force of magnitude F applied at an angle of θ = 30° with the horizontal, as shown in the figure below. If the coefficient of kinetic friction between block and wall is 0.30, determine the ...
*March 2, 2016 by sherry*

**French, foreign language**

Hi, I need help with answering some questions for French Here's my work on them tell me what you came up with for each question that is incorrect: 1.C'est un plat typiquement français. On les prépare avec du beurre et de l'ail. Ce sont un escargot (incorrect) 3.Ce sont des lé...
*March 17, 2015 by Alex*

**physics**

1.) A 7159 N piano is to be pushed up a(n) 2.26 m frictionless plank that makes an angle of 25.6 degrees with the horizontal. Calculate the work done in sliding the piano up the plank at a slow constant rate. Answer in units of J. 2.) A 20 g bullet is accelerated in a rifle ...
*November 18, 2015 by Balta*

**Chemistry**

An atmospheric scientist interested in how NO is converted into NO2 in urban atmospheres carries out two experiments to measure the rate of this reaction. The data are tabulated below. A: [NO]0 = 9.63 × 10-3 M, [O2]0 = 4.1 × 10-4 M t(s) 0/3.0/6.0/9.0/12.0 [O2] 4.1/2.05/1.02/0....
*February 23, 2012 by help*

**Chemistry **

An atmospheric scientist interested in how NO is converted into NO2 in urban atmospheres carries out two experiments to measure the rate of this reaction. The data are tabulated below. A: [NO]0 = 9.63 × 10-3 M, [O2]0 = 4.1 × 10-4 M t(s) 0/3.0/6.0/9.0/12.0 [O2] 4.1/2.05/1.02/0....
*March 2, 2014 by Serena*

**Physics**

All answers should be in degrees. (a) Using the result of Lecture 31 Question 3, and Snell's law, derive and evaluate for the secondary rainbow for the following values of the incidence angle and index of refraction . 1 , 1.4 incorrect 45 , 1.3 incorrect 87 , 1.55 incorrect (...
*June 5, 2013 by P*

**chemistry**

What is the rate of the following reaction (M/s) if the rate constant for the reaction is 0.500 L•mol-1•s-1 and the concentration of each reactant is 0.0628 M. (The units for the rate constant depend upon the rate law). CO + NO2 --> CO2 + NO
*November 20, 2010 by Confused*

**chemistry**

A 50-mL Mohr buret is connected to a 1-ft length of capillary tubing. The buret is then filled with water and the volume of water versus time is monitored as the water gradually flows through the capillary tubing. This process is found to be first-order with a rate constant of...
*May 16, 2010 by eng*

**Statistics**

A sample of 148 values is randomly selected from a population with mean, μ, equal to 46 and standard deviation, σ, equal to 17. (Give your answers correct to one decimal place.) (a) Determine the interval (smallest value to largest value) within which you would ...
*November 23, 2014 by Dakota*

**Math**

Does studying for an exam pay off? The number of hours studied, x, is compared with the exam grade received, y. x 7 7 5 5 7 y 95 90 75 85 95 (a) Complete the preliminary calculations: SS(x), SS(y), and SS(xy). Incorrect: Your answer is incorrect. . (SS(x)) Incorrect: Your ...
*May 30, 2013 by Krista*

**Math PLEASE help**

Does studying for an exam pay off? The number of hours studied, x, is compared with the exam grade received, y. x 7 7 5 5 7 y 95 90 75 85 95 (a) Complete the preliminary calculations: SS(x), SS(y), and SS(xy). Incorrect: Your answer is incorrect. . (SS(x)) Incorrect: Your ...
*May 30, 2013 by Krista*

**rate constant**

A reaction has a rate constant of 1.25×10−4 at 28 and 0.227 at 77. Determine activation barrier for reaction What is the value of the rate constant at 18?
*February 10, 2013 by charlie*

**Temperature Problem**

Q: A reaction rate has a constant of 1.23 x 10-4/s at 28 degrees C and 0.235 at 79 degrees C. Determine the activation barrier for the reaction. A: My work thus far: ln(1.23 x 10-4/0.235)=(Ea/8.314)(1/301.15-1/352.15) -7.551=(Ea/8.314)(0.0048090535) -7.551=(Ea/8.314)(0....
*February 2, 2013 by Amy*

**CHEM**

Which of the following will be affected by the addition of a catalyst to a chemical reaction? Choose all that apply. thanks A)the magnitude of the equilibrium constant B) the value of the ratio kf/kr C) ÄHo D) ÄSo E) the value of the forward rate F) the value of the reverse ...
*May 29, 2010 by Adam*

**Chemistry **

An atmospheric scientist interested in how NO is converted into NO2 in urban atmospheres carries out two experiments to measure the rate of this reaction. The data are tabulated below. A: [NO]0 = 9.63 × 10-1 M, [O2]0 = 4.1 × 10-4 M t(s) 0/3.0/6.0/9.0/12.0 [O2] 4.1/2.05/1.02/0....
*February 18, 2016 by Jesse*

**Chemistry**

Which of the following will be affected by the addition of a catalyst to a chemical reaction? a. ÄGo b. the value of the reverse rate constant, kr c. the value of the reverse rate d. the value of the ratio kf/kr e. the value of the forward rate f. the value of the forward rate...
*May 30, 2010 by John*

**chemistry**

Which of the following sets of quantum numbers are not allowed. For each incorrect set, state why it is incorrect. For each correct set, name the atomic orbital. i. n=4, l=3, ml =2, ms =-1/2 ii. n=2, l=1, ml =-1, ms =-1 iii. n=5, l=-4, ml =2, ms =+1/2 can you guys help me my ...
*June 26, 2016 by lo*

**Chemistry**

A second order reaction has a rate constant of 8.7x10^-4/(M*s) at 30 degrees C. At 40 degrees C the rate constant is 1.8x10^-3/(M*s). What are the activation energy and frequency factor for this reaction? Predict the value of the rate constant at 4 degrees C
*February 29, 2008 by Lauren*

**Calculus**

Oil spilled from a ruptured tanker spreads in a circle whose area increases at a constant rate of 7.5 mi^2/hr. How rapidly is radius of the spill increasing when the area is 8 mi^2? I tried using A=(pi)r^2 and dA/dt=2(pi)r(dr/dt) and plugging in 7.5=2(pi)8(dr/dt) but the ...
*April 10, 2015 by Ashley*

**chemistry**

disappearance of NO in ...- Help!!!? The following data were collected for the rate of disappearance of NO in the reaction 2 NO(g) + O2(g) ¨ 2 NO2(g). Run: [NO](M) [O2](M) Initail Rate (M/s) 1 .0126 .0125 1.41 X 10^-2 2 .0252 .0125 5.64 X 10^-2 3 .0252 .0250 1.13 X 10^-1 (a) ...
*January 30, 2013 by Hannah*

**Chemistry**

2A-->B+C given that the initial concentration of A is .022M and that at 69 s, the concentration of B increases to .0095M, what is the rate constant? i know I need to find the new concentration of A at 69s, but I am having trouble with findthing this. I thought it might be ...
*March 31, 2010 by Val*

**Chemistry **

A 50-mL Mohr buret is connected to a 1-ft length of capillary tubing. The buret is then filled with water and the volume of water versus time is monitored as the water gradually flows through the capillary tubing. This process is found to be first-order with a rate constant of...
*May 18, 2010 by anonymous*

**Chemistry **

A 50-mL Mohr buret is connected to a 1-ft length of capillary tubing. The buret is then filled with water and the volume of water versus time is monitored as the water gradually flows through the capillary tubing. This process is found to be first-order with a rate constant of...
*May 18, 2010 by anonymous*

**Temperature**

Q: A reaction rate has a constant of 1.23 x 10-4/s at 28 degrees C and 0.235 at 79 degrees C. Determine the activation barrier for the reaction. A: My work thus far: ln(1.23 x 10-4/0.235)=(Ea/8.314)(1/79-1/28) -7.551=(Ea/8.314)(0.01265-0.03571) -7.551=(Ea/8.314)(-0.02305) 327....
*February 1, 2013 by Amy*

**Physics**

Three parallel plate capacitors (C1,C2 and C3 ) are in series with a battery of 100 V. C1=2500 micro Farad; C2=2C1 , C3=3C1 . (a) What is the potential difference over each capacitor and how much charge is on each capacitor? Across C1 :V1 (in Volts) = incorrect Q1 (in C) = ...
*March 13, 2013 by P*

**calculus**

a 20 ft ladder is leaning against a wall. The bottom is being pulled out at a constant rate of 2.5 ft/sec. Will the top of the ladder clide sown thr wall at a constant rate? What will the rate be? In relation to time? It is not constant. Use pythagorus: x^2 + y^2 = l^2, where ...
*October 12, 2006 by Suzy*

**CHEMISTRY**

A second-order reaction has a rate constant of 1.65 M–1 s–1. If the initial reactant concentration is 1.0 M, calculate the time (in seconds) required for the reaction to become 90% complete. i got 0.06734 seconds but thats incorrect i have no idea what i am doing wrong! HELP!!!!
*March 28, 2012 by Maya *

**ECON**

You’ve recently learned that the company where you work is being sold for $500,000. The company’s income statement indicates current profits of $25,000, which have yet to be paid out as dividends. Assuming the company will remain a “going concern” indefinitely and that the ...
*September 7, 2015 by Chante*

**Chemistry**

the activation energy for the decomposition of HI(g) to H2(g) and I2(g) is 186kj/mol. the rate constant at 555k is 3.42 x 10^-7 L/mol*s. What is the rate constant at 645K? Please show all steps USING THE ARRHENIUS EQUATION. Here is my work so far: K = A e^(-Ea/RT) 3.52 x 10^-...
*October 26, 2010 by Jim*

**chemistry**

A first-order reaction is 40% complete at the end of 50 minutes. What is the value of the rate constant (in min^-1)? A. 1.8 x 10^-2 B. 1.0 x 10^-2 C. 1.2 x 10^-2 D. 8.0 x 10^-3 E. none of these how would i approach this problem? i know that to find the rate constant, i could ...
*May 26, 2008 by jesse may*

**chemistry**

You mix together in the proper manner the following VOLUMES: 0.0100 M Potassium iodide...9.2 mL 0.0010 M Sodium thiosulfate...6.5 mL Distilled water...16.8 mL 0.0400 M Potassium Bromate...13.9 mL 0.100 M Hydrochloric acid...6.1 mL Using the rate constant and rate equation ...
*March 2, 2013 by Cassie*

**physics**

A man pushing a crate of mass m = 92.0 kg at a speed of v = 0.845 m/s encounters a rough horizontal surface of length scripted l = 0.65 m as in the figure below. If the coefficient of kinetic friction between the crate and rough surface is 0.357 and he exerts a constant ...
*June 3, 2013 by Melissa*

**Chemistry**

1) Three factors control the rate of evaporation of a liquid: surface area, temperature, and strengths of intermolecular forces. More than one of the statements given described a correct effect. The statements are (1) the larger the surface area, the faster the rate of ...
*January 30, 2012 by Hannah*

**chemistry(check my answer)**

Which of the following will be affected by the addition of a catalyst to a chemical reaction? a)the value of the reverse rate constant, kr b)the magnitude of the equilibrium constant c)the value of the forward rate d)ΔHo e)the value of the forward rate constant, kf f)&#...
*May 14, 2010 by eng*

**MATH**

what is a constant rate of change? That means the velocity changes over time in the same manner. 4,800 +3,700 =4,500 Rate of Change Is Constant You can increase or decrease the amount or concentration of a species by a constant value using a zero order rule. For example, the ...
*January 9, 2007 by Austin*

**math answer check**

x is a binomial random variable. (Give your answers correct to three decimal places.) (a) Calculate the probability of x for: n = 1, x = 0, p = 0.15 P(x) = Changed: Your submitted answer was incorrect. 0.15 x 0 = 0 . (b) Calculate the probability of x for: n = 3, x = 3, p = 0....
*June 1, 2013 by Nora 57*

**Economics**

“Many countries peg their own currencies to the greenback; these countries import U.S. inflation when the Fed makes a mistake.” Why would these countries “import” inflation. A. this is incorrect because countries only import goods or services B. this is correct because a fixed...
*March 27, 2011 by CLA*

**Chemistry **

A reaction has a standard free-energy change of –10.30 kJ mol–1 (–2.462 kcal mol–1). Calculate the equilibrium constant at 25ºC.? This is what I've done so far.. ∆Gº= -2.3 RT + log (K) -10.31 kJ = -2.3 (.0083145)(298) + log K -10.31 kJ = -2.3 (2.48) log K log K = 10.31kJ...
*March 18, 2014 by Angely R. *

**AP physics c**

A helicopter lifts a 63 kg astronaut 10 m vertically from the ocean by means of a cable. The acceleration of the astronaut is g/10. (a) How much work is done on the astronaut by the force from the helicopter? Incorrect: Your answer is incorrect. J (b) How much work is done on ...
*October 10, 2013 by please help*

**Chem II**

The equilibrium constant of a reaction is 12.6. If the rate constant of the reverse reaction is 5.1 x 10 -2 the rate constant for the forward reaction is _____ 0.32 0.16 0.64 0.08 I don't even know where to start on this question. Any direction will help
*June 16, 2008 by Ken*

**Math help**

Find the 98% confidence interval for estimating ìd based on these paired data and assuming normality. (Give your answers correct to one decimal place.) Before 50 55 61 52 68 54 After 34 58 56 36 40 39 Lower Limit Incorrect: Your answer is incorrect. 64.0 Upper Limit Incorrect...
*June 23, 2013 by tracy10*

**business**

You have recently learned that the company where you work is being sold for $275,000. The company’s income statement indicates current profits of $10,000 which have yet to be paid out as dividends. Assuming the company will remain a “growing concern” into the infinite future ...
*January 7, 2012 by john*

**Finding the Activation Barrier**

Q: A reaction rate has a constant of 1.23 x 10-4/s at 28 degrees C and 0.235 at 79 degrees C. Determine the activation barrier for the reaction. A: My work thus far: ln(1.23 x 10-4/0.235)=(Ea/8.314)(1/79-1/28) -7.551=(Ea/8.314)(0.01265-0.03571) -7.551=(Ea/8.314)(-0.02305) 327....
*January 31, 2013 by Amy*

**calculus**

Boyle's law states that if the temperature of a gas remains constant, then PV = c. Where P is the pressure, V is the volume, and c is a constant. Given a quantity of gas at constant temperature, if V is decreasing at a rate of 13 in.^3/s, at what rate is P increasing when P = ...
*May 2, 2010 by Hussain*

**Chemistry**

calculate the rate constant at 225C for a reaction that has a rate constant of 8.1X10^-4 at 95c and an activation enegry of 93.0 kj/mol
*June 8, 2013 by Jason*

**chemistry **

A reaction has a first order rate constant of 6.11x10-5 s-1 at 25C and 0.00221 s-1 at 85oC. What is the value of the rate constant at 63oC?
*June 14, 2016 by Basil*

**make check**

Consider the following. (Give your answers correct to four decimal places.) (a) Determine the level of confidence given the confidence coefficient z(á/2) for z(á/2) = 1.65. Incorrect: Your answer is incorrect. . 0.90 is what I got and it was wrong, I have several like this if ...
*June 18, 2013 by Tom 84*

**math formulas needed**

Use the following table to answer the questions. (Give your answers correct to two decimal places.) x 1 1 3 3 5 5 7 7 9 9 y 3 2 6 1 3 3 3 2 5 3 (a) Find the equation of the line of best fit. y hat = + x (ii) Graph this equation on a scatter diagram. (Do this on paper. Your ...
*June 18, 2013 by Tom 12*

**Chemistry Lab**

What would happen to the reaction rate of a solution if 10 mL or more of water is added? Will the reaction rate increase or decrease? The following reaction occurs without a change in the color 2A (g) + B2(g) --- 2AB (g) a) How could you monitor the concentration of the ...
*July 20, 2009 by Sunshine*

**Chemistry Lab**

What would happen to the reaction rate of a solution if 10 mL or more of water is added? Will the reaction rate increase or decrease? The following reaction occurs without a change in the color 2A (g) + B2(g) --- 2AB (g) a) How could you monitor the concentration of the ...
*July 20, 2009 by Sunshine*

**java programming**

You need to provide more than a yes or no answer for this question. Consider both the selection sort and the bubble sort. If these algorithms will work with duplicates explain why they will still work. If they will not work, explain why they will not work. If one will work and...
*July 29, 2006 by george*

**chemistry**

The rate constant of a first-order reaction is 4.25 x 10^-4 s^-1 at 350 Celsius. If the activation energy is 103 kJ/mol, calculate the temperature at which its rate constant is 8.75 x 10^-4 s^-1.
*March 25, 2014 by santoki*

**gen chem**

The rate constant of a first order reaction is 4.60 x 10-4 s-1 at 350 oC. If the activation energy is 104 kJ/mol, calculate the temperature in Kelvin at which its rate constant is 1.80 x 10-3 s-1.
*February 22, 2016 by Anonymous*

**college chemistry**

The rate of the following reaction: 2 NO2 2 NO + O2, is characterized by the rate constant k = 0.775 L·mol-1s-1. What is the half-life for this reaction at the same conditions when the initial concentrations are 0.0115 M? (Round your answer to 3 significant figures.) Hint: The...
*November 10, 2010 by sparkle*

**Chemistry **

Decomp. of H2O2 with Catalase.I am trying to use the Arrhenius equation in my coursework, but i am struggling to get it to work. I have substituted most of the information in, such as activation energy(23000J), and gas constant(8.314x10-3) etc. The issue is "A" which is the ...
*February 27, 2011 by Suriya *

**algebra**

A principal of $5000 was invested in a savings account for 4 years. If the interest earned for the period was $400, what was the interest rate? i know this is 1.5 % or at least I think it is but how do i write it out? Use the equation I=Prt, where I=interest earned, P=...
*May 30, 2007 by confused*

**calc**

2- The earth’s atmospheric pressure p is often modeled by assuming that the rate dpdhat Which p changes with the altitude above sea level is proportional to hp. Suppose that the pressure at sea level is 1013 millibars (about 14.7 pounds per square inch) and that the pressure ...
*April 10, 2007 by barb*

**Physical Science**

A 20.0-Ù resistor and a 45.0-Ù resistor in parallel are connected to a 120-V dc source. (a) What is (are) the current(s) through the resistors? current through the 20.0-Ù resistor: Incorrect: Your answer is incorrect. . A current through the 45.0-Ù resistor: Incorrect: Your ...
*March 30, 2016 by Brian*

**chemistry**

For a certain chemical reaction, the rate constant at 250.0 °C is 0.00383 s-1 and the activation energy is 22.40 kilojoules. Calculate the value of the rate constant at 335.0 °C. a. 0.00513 s-1 b. 0.00946 s-1 c. 0.00787 s-1 d. 0.0224 s-1 e. 0.000640 s-1 b or c
*February 24, 2012 by bob*

**Chemistry**

At 700 k the equilibrium constant Kc for the reaction between NO(g) and O2(g) forming NO2(g) is 8.7*10^6. The rate constant for the reverse reaction at this temperature is 0.54 M^(-1)s^(-1). What is the value of the rate constant for the forward reaction at 700 K?
*March 12, 2016 by Shay*

**Chemistry **

A certain reaction has an activation energy 52.93 kJ/mol. At what kelvin temperature will the reaction proceed 8.00 times faster than it did at 315K? Ea = 52.93 kJ/mol = 52930J R (gas constant) = 8.314 T1 = 315K k1 = rate constant at T1 T2 = ? k2 = rate constant at k2 = 8.00 ...
*March 17, 2015 by Jessica*

**math check**

Suppose that you are in a class of 31 students and it is assumed that approximately 13% of the population is left-handed. (Give your answers correct to three decimal places.) (a) Compute the probability that exactly five students are left-handed. Incorrect: 9.936 (b) Compute ...
*June 13, 2013 by Tom56*

**Chemistry**

Which statement about Kc is wrong? A. Kc is always a constant B. For some reactions, Kc increases with temperature increase C. For some reactions, Kc decreases with temperature decrease D. For some reactions, Kc changes when pressure is changed A is incorrect. Kc stays ...
*January 31, 2007 by Joe*

**Algebra 1**

using a constant rate, you can saw a log into 3 pieces in 12 minutes. At the sam constant rate, how long will it take you to cut a siliar log (if the same size) into 6 pieces? would you do a rate formula or what? I'm really stuck on this one!
*May 20, 2008 by Libby*

**chemistry**

Values of the rate constant for the decomposition of N2O5 at four different temperatures are as follows: T(K) k(s^-1) 658....2.14*10^5 673....3.23*10^5 688....4.81*10^5 703....7.03*10^5 The activation energy is 1.02*10^2 kJ/mol. Calculate the value of the rate constant at 300 K
*October 14, 2012 by Brunette *

**differential calculus**

a SECURITY CAMERA is centered 50 feet above a 100-foot hallway. it is easiest to design the camera with a constant angular rate of rotation, but this results in a variable rate at which the images of the surveillance area are recorded. so, it is desirable to design a system ...
*September 16, 2014 by =)*

**Chemistry**

An excited ozone molecule, O3*, in the atmosphere can undergo one of the following reactions, O3* → O3 (1) fluorescence O3* → O + O2 (2) decomposition O3* + M → O3 + M (3)deactivation, where M is an inert molecule, the rate constant for the fluorescence ...
*December 5, 2015 by Anonymous*

**Chemistry**

An excited ozone molecule, O3*, in the atmosphere can undergo one of the following reactions, O3* → O3 (1) fluorescence O3* → O + O2 (2) decomposition O3* + M → O3 + M (3)deactivation, where M is an inert molecule, the rate constant for the fluorescence ...
*December 7, 2015 by Anonymous*

**chemistry**

The reaction 2NOCl(g) ¨ 2NO(g) + Cl2 (g) has an activation energy of 100.0 kJ/mol and a rate constant at 350.0 K of 8.5 x 10-6 mol-1 L s-1. Determine the rate constant at 400 K.
*February 9, 2010 by G-Unit 32*

**Chemistry**

the activation energy for the decomposition of HI(g) to H2(g) and I2(g) is 186kj/mol. the rate constant at 555k is 3.42 x 10^-7 L/mol*s. What is the rate constant at 645K? Please Show all Steps! thank you!
*October 26, 2010 by Jack*

**Chem II**

The rate constant for a reaction at 305.0 K is two times the rate constant at 295.0 K. The activation energy of the reaction is ______ kJ mol
*June 13, 2008 by Ken*

**chemistry**

calculate the rate of a constant reaction at 293 kelvin when the energy of activation is 103 kilo joules per mole and the rate constant at 273 kelvin is 7.87*10 to the power -7...
*January 24, 2013 by Emeldah*

**chemistry**

calculate the rate of a constant reaction at 293 kelvin when the energy of activation is 103 kilo joules per mole and the rate constant at 273 kelvin is 7.87*10 to the power -7...
*January 24, 2013 by Emeldah*

**chemistry**

If a reaction has rate constant of 1.33 s^-1 at 206 deg C and an activation energy of 58.6 kj mol^-1. whats the rate constant at 358 deg C ?
*July 23, 2014 by Ann*

**chemistry**

The following experimental data were obtained for the reaction; 2 NO + 2 H2 ¡æ N2+ 2 H2O Rate/10-5M/s [NO]/10-2M [H2]/10-2M 0.50 0.50 0.20 2.00 1.00 0.20 0.25 0.25 0.40 Write a rate law in agreement with the data. Rate = What is the value and units of the rate constant?
*February 1, 2015 by jhon*

**Concentration and Reaction**

The rate of the following reaction: Radioactive decay of 90Sr, is characterized by the rate constant k = 0.024 year-1. What is the half-life (in years) for this reaction at the same conditions when the initial concentrations are 0.0356 M? (Round your answer to 3 significant ...
*November 20, 2010 by Confused*

**Physics**

Point charges Q1 ,Q2 , and Q3 reside on three corners of a square with sides of 1m ; the distance from Q2 to P3 is 2m (see diagram). (a) What is the electric potential,V , at P1 ? (Normalize the potential to be zero at infinity and give your answers in Volts). incorrect What ...
*March 5, 2013 by P*