Posts by Rachel

Total # Posts: 1,553

CHEMISTRY
A buffer that is 0.271 M in acid, HA, and 0.150 M in the potassium salt of its conjugate base, KA, has a pH of 2.85. What is the pH of the buffer after 130. mL of 0.155 M LiOH is added to 0.650 L of this buffer? Assume that the volumes are additive.

Math: Different Forms of Linear Functions
y< x/2 -6 How do I make this into a table and then into ordered pairs?

Math: Different Forms of Linear Functions
The output is 6 less than one-half of the input

chemistry
What is Delta H rxn for the following chemical reaction? H2O(l) + CCl4(l)-> COCl2(g) + 2HCl(g)

math
cos(2x)

math
solve for sinx=cos2x (between 0 and 2pi)

calculus
find cosx and sinx if tanx = 4

Math

Math
7th* Hahaha The answer is onee![:

Math
Highest number minus the lowest. Which would be 5-4 You're Welcome!(; Btw I'm like a 7h graderr.:P

math
But what if you pull out four of one color socks?

calculus
The side of a square is measured to be 12 inches with a possible error of ±0.02 inch in that measurement. If x is the exact length of the side of the square, express this difference as an absolute value inequality and solve. Then find the interval expressing the range ...

Bio
What is it called when b=d and r=0? A. iteroarity B. semelparity C. zero population growth D. cohort E. a survivorship curve I think it is E but I would greatly appreciate a teacher's input!

Chemistry
an atom is to an element as a compound is to a?

English
Thank you! It's really nice that you do this whole homework help for free. A lot of websites charge for stuff like that! I appreciate it immensely:) I'll be keeping this website in mind when I have Algebra 3-4 to keep up with:P

English
What tools are in a "writing toolbox"?

Medical Terminology
Need help identifying 15 medical terms that would be unfamiliar to non-medical persons. Also providing singular and plural forms of selected medical terms. This is a 47-year-old male who was in his usual state of health until early this evening when he developed an acute ...

Trigenometry

algebra
4000

intermediate icd 9 cm coding
What are the codes for Intrauterine pregnancy, spontaneous delivery, single live born?

Med terms
dysphnea=dyspnea.....oops

Med terms
afonia=pneumonia eupnia=apnea dysphnea=dyspnes DOT=DOB ventolator=ventilator

Med terms
I am having troubles finding all 10 mistakes and need some help. Inpatient Progress Report Attending Physician: Moreover, Cindy Patient: Stephen R. Peters DOT: 03/01/19XX CHIEF COMPLAINT: This 53-year-old man visited the outpatient clinic for dyspnea and recurrent coughing. ...

physics
Physics: maximum force that can be applied to move an object? What is the maximum force F which can be exerted? Given: The friction between the block with mass 14 kg and the wedge with mass 16 kg is 0.19 . The surface between the wedge with mass 16 kg and the horizontal plane ...

Life science
True or false, the healthiest position to sleep on for the baby while you're pregnant is on your back

Life science
How many teeth does a child have and how many teeth do adults have?

Math puzzle
2•2=4, 7•3=21, 4•3=12, 3•2=6 ... 4+21=25, 25+12= 37, 37+3= 40, 40+4=44, 44+6= 50... I'm no math genius but I hope that I helped, the answer is 50.

propability
there are 40 tags numbered 1 through 40 in a bag. what is the probability that Glenn will randomly pick a multiple of 5 and than a multiple of 9 without replacing the first one?

Physics (Fill in the Blanks)
1. The last stage of a giant star is ____ 2. The path of a satellite is called ____ 3. The size of the Sun is the result of the "tug of war" between two opposing processes, nuclear fusion and ____ contraction Thanks :)

Physics
Two students are on a balcony 20.5 m above the street. One student throws a ball (ball 1) vertically downward at 11.1 m/s; at the same instant, the other student throws a ball (ball 2) vertically upward at the same speed. The second ball just misses the balcony on the way down...

Chem
Calculate the standard cell voltage, Eo, for the following reactions. Include the sign of the voltage in your answers. (a) Fe2+(aq) + Pb(s) --> Pb2+(aq) + Fe(s)

Chemistry
2 Ag+(aq) + Fe(s) --> 2 Ag(s) + Fe2+(aq) Which electrode is the anode, and which is the cathode. and In which directions do the cations and anions migrate through the solution? cations thanks

Mary and Celia open a boutique, they hire independent contractors. When they are not selling Mary and Celia want the I.C's to do inventory and clean up the boutique. Mary and Celia also set the working hourse.. does these factors affect theri status as independent ...

chemistry
In the reaction 2SO2 (g) + O2 (g) 2SO3 (g), which change would cause the greatest increase in the concentration of SO3?

Brief Calculus
its supposed to be 1/v^7

Brief Calculus
Evaluate the integral. HINT [See Example 2 and 4.] (Remember to use ln |u| where appropriate.) (1/v7 + 5/v) dv

Calc
Find f(x) if f(1) = −1 and the tangent line at (x, f(x)) has slope7ex + 6. F(x)=

Calculus
no it is just as the denominator is one with the variable 4x^5 and 2x^7 not 1/25 raised to the 6th or 1/2 raised to the 7th

Calculus
Use fundamental theorem of calculus: Int(pi/2_pi) of e^(sin(q))*cos(q)dq

Chemistry
In the following reaction, how many grams of ammonia (NH3) will produce 300 grams of N2? 4NH3 + 6NO d 5N2 + 6H2O

Algebra
Explain the difference in answers between the following exponential expressions. Include the solutions? 7^2, -7^2,(-7)^2, and 7^-2

Well I've got 8,2,9,3,1,6,10,4,7,5. Do you think this is correct?

This is not in order. Please put the story about "The wishing well in order" 1. Today is a particularly busy day at the well. 2. This wishing well is very popular 3.It is New Years Day 4.Other People make wishes about their families. 5. For this reason the park will ...

Religion and Spirituality
What do you think is the moral of the story Tao of Forgiveness? Thank you :)

Math
determine one value of c that allows the trinomial cy^2 + 36y - 18 to be factored over the integers

Math
oh and the other rectangle is 1 by 5 ft

Math
1 by 8 is the dimensions I drew them both and divided the perimeters and then substitued starting from 1 and it worked the first time, but yeah the answer is 8

Geometry
how to you solve: the radius of circle Z is 13.5 units long. Find the length of each arc for the given angle measure. if the angle measure is 120 degrees?

Calculus
Hey, we covered limits at the beginning of the year, but I cannot remember how to do them at all. >>>what is the limit, as x approaches 2, of ((1/x )-(1/2))/(x-2)? Please go step by step!

math
a cross section of a hollow circular pipe shows that its inner diameter is 2 1/10inches and that the pipe is 3/5inch thick. what is the outside diameter

economics
Jerry will receive the following payments: 946 in year 3, 929 in year 5 and 958 in year 9. What is the purchasing power of the present value of these payments if the market interest rate is 17% per year and the inflation rate is 6% per year?

economics
Tom plans to gamble each year for the next 20 years, starting at at the end of year 1. If he loses 4.47 dollars in odd years (i.e., years 1, 3, 5, etc) and wins 7.46 dollars in even years (i.e., years 2,4, 6 etc), what will be Tom's (internal) rate of return per year from ...

economics
Consider a project with a positive rate of return. Suppose the discount factor solutions to the equation which determines the internal rate of return (ROR) of the project are given by 0.8502, 2.0207, -0.1767. What is the project's ROR?

Chem (repost)
Hydrogen and carbon dioxide react at a high temperature to give water and carbon monoxide. H2(g) + CO2(g) --> H2O(g) + CO(g) (b) Suppose 0.052 mol each of H2 and CO2 are placed in a 1.5 L container. When equilibrium is achieved at 986°C, what amounts of CO(g) and H2O(g...

Chemistry(check my work)?
An equilibrium mixture of the following reaction was found to have [COF2] = 0.255 M and [CF4] = 0.118 M at 1000°C. What is the concentration of CO2? 2 COF2(g) ---> CO2(g) + CF4(g) Keq = 2.00 at 1000°C I know I need to put the numbers in the equation so this is what ...

How many sig figs?
Thanks:)

How many sig figs?
An equilibrium mixture of the following reaction was found to have [H2] = 0.020 M and [I2] = 0.020 M at 340°C. What is the concentration of HI? H2(g) + I2(g)--> 2 HI(g) Keq = 69 at 340°C I got .166 but it said check number of sig figs so im guessing its 2 sig figs ...

chem
Sorry I am soo confused right now O.O. is there anyway u can explain this in simplier form?

chem
ok so I did (x)(x)/(.03466)(.03466)= 1.6. I solved for x and got .0438. Do I have to do anything with this number to get the correct answer? Can you check my work? Thanks:)

chem
thanks Would you get the same answer for both parts of b?

chem
Hydrogen and carbon dioxide react at a high temperature to give water and carbon monoxide. H2(g) + CO2(g) --> H2O(g) + CO(g) (a) Laboratory measurements at 986°C show that there are 0.11 mol each of CO and H2O vapor and 0.087 mol each of H2 and CO2 at equilibrium in a 1...

Chemistry
Nevermind I got it:)

Chemistry
An equilibrium mixture of SO2, O2, and SO3 at 1000 K contains the gases at the following concentrations: [SO2] = 3.77 10-3 mol/L, [O2] = 4.30 10-3 mol/L, and [SO3] = 4.13 10-3 mol/L. Calculate the equilibrium constant, K, for the following reaction. 2 SO2(g) + O2(g) ---> 2 ...

science
I am really confused on this too. I'm pretty sure you come from Connections Academy. What I did was gon on google and search saturated and unsaturated. It should help a bit?

chemistry
4.56x10-2g Na.

Chemistry (repost)
Which of the following pairs of substances, when mixed in any proportion you wish, can be used to prepare a buffer solution? 1)NaCN and NaOH 2) HCl and NaOH 3) HCN and NaOH 4)HCl and NaCN 5) NaCN and HCN is the answer 1 and 5?? chem - DrBob222, Sunday, April 10, 2011 at 1:28am...

chem
I tried those and it was wrong

chem
Which of the following pairs of substances, when mixed in any proportion you wish, can be used to prepare a buffer solution? 1)NaCN and NaOH 2) HCl and NaOH 3) HCN and NaOH 4)HCl and NaCN 5) NaCN and HCN is the answer 1 and 5??

physics
Two very long, straight, parallel wires carry currents that are directed perpendicular. Wire 1 carries a current I1 into the page (in the -z direction) and passes through the x axis at x = +a. Wire 2 passes through the x axis at x = -2a and carries an unknown current I2. The ...

physics
A Hall-effect probe operates with a 120 -mA current. When the probe is placed in a uniform magnetic field of magnitude 0.0840 T, it produces a Hall voltage of 0.660 µV. The thickness of the probe in the direction of B is 2.00 mm. Find the density of the charge carriers, ...

physics
oh alright sir thank you!

physics
An accelerating voltage of 2.46 * 10^3 V is applied to an electron gun, producing a beam of electrons originally traveling horizontally north in vacuum toward the center of a viewing screen 34.0 cm away. What is the magnitude of the deflection on the screen caused by the ...

Physics
Thank you for your help. I am still unsure on the formulas I am meant to be using and when I am meant to be converting from mmHg to Pa.

Physics
I have been given this question and with very little knowledge of physics and a book and flex studies that I am not finding very explanitory. I am not sure I am on the correct path as the vlaues I have seem very large. I would appreciate any help/assistance anyone could give. ...

physics
A Hall-effect probe operates with a 120 -mA current. When the probe is placed in a uniform magnetic field of magnitude 0.0840 T, it produces a Hall voltage of 0.660 µV. The thickness of the probe in the direction of B is 2.00 mm. Find the density of the charge carriers, ...

physics
An accelerating voltage of 2.46 * 10^3 V is applied to an electron gun, producing a beam of electrons originally traveling horizontally north in vacuum toward the center of a viewing screen 34.0 cm away. What is the magnitude of the deflection on the screen caused by the Earth...

physics
An accelerating voltage of 2.46 * 10^3 V is applied to an electron gun, producing a beam of electrons originally traveling horizontally north in vacuum toward the center of a viewing screen 34.0 cm away. What is the magnitude of the deflection on the screen caused by the Earth...

physics
A Hall-effect probe operates with a 120 -mA current. When the probe is placed in a uniform magnetic field of magnitude 0.0840 T, it produces a Hall voltage of 0.660 µV. The thickness of the probe in the direction of B is 2.00 mm. Find the density of the charge carriers, ...

Chemistry
Find the Ph: of 7.01 x 10-5 M Ba(OH)2 thanks:)

calculus
what is the integral of [e^(11x)]/[e^(11x)+8]

Chemistry!
a microwave oven uses electromagnetic radiation with a wavelength of 3.00x10^6 nm. calculate energy (in joules) of 1.65 moles of photons of this radiation.

physics
sir i read through the site so when i use force 0 how should i solve this question? thank you

physics
An accelerating voltage of 2.46 * 10^3 V is applied to an electron gun, producing a beam of electrons originally traveling horizontally north in vacuum toward the center of a viewing screen 34.0 cm away. What is the magnitude of the deflection on the screen caused by the Earth...

physics
so sir in this formula. I = 120mA B = 0.0840 T n = 8.47 * 10^28 q = 1.6 * 10 ^ -19 t = 2.00 mm but how do i calculate d?

physics
sir should i use this formula V = IB/nqt thanks you

physics
oh ok sir thank you. The thickness of the probe in the direction of B is 2.00 mm. Find the density of the charge carriers, each of which has charge of magnitude e). thank you again sir

physics
A Hall-effect probe operates with a 120 -mA current. When the probe is placed in a uniform magnetic field of magnitude 0.0840 T, it produces a Hall voltage of 0.660 µV. When it is used to measure an unknown magnetic field, the Hall voltage is 0.360 µV. What is the ...

geometry
what is the area of a circle with a circumference of 22 pi in.? expressed in pi in. squared? and what are the steps to arrive at the solution?

Math
10^-8

Chemistry.
The complete combusion of 0.5763 grams of glucose in a bomb calorimeter (Cbomb = 6.20 kJ/degrees C) raises the temperature of the calorimeter by 1.45 degrees C. what is the food value of glucose in calories per gram? (Hint: remember 1 Cal = 4.184 kJ) i do not know how to find ...

Geometry
1. Graph the quadrilateral with vertices C(-9,4), D(-4,8), E(2,6), and F(-3,2). What specific shape is it? 2. Include the work with explanations of how you solved this. 3. List at least 2 other ways you could have proved this. You do not have to prove these additional ways, ...

The combusion of glucose produces carbon dioxide and water vapor according to the chemical equation below: C6H12O6 (s) + 6O2 (g) ---> 6CO2 (g) + 6H2O (g) DELTA H = -2540 kj Calculate the energ involved in making 75.0 g of glucose from carbon dioxide and liquid water (...

economics
What is the face value of a municipal bond that has a bond (or coupon) interest rate of 6% per year and makes interest payments of 578 dollars every 1 months?

physics
A proton moves at 3.60 *10^5 m/s in the horizontal direction. It enters a uniform vertical electric field with a magnitude of 8.20* 10^3 N/C. Find the time interval required for the proton to travel 4.00 cm horizontally. thanks

physics
A uniform electric field of magnitude 320 V/m is directed in the negative y direction. The coordinates of point A are (-0.300, -0.450) m, and those of point B are (0.650, 0.300) m. Calculate the electric potential difference VB − VA. thanks

physics
A copper wire has a circular cross section with a radius of 3.75 mm. If the wire carries a current of 4.00 A, find the drift speed of the electrons in the wire. (Assume the density of charge carriers (electrons) in a copper wire is n = 8.46 *10^28 electrons/m^3.) thanks

physics
An electron moving parallel to the x axis has an initial speed of 4.82 *10^6 m/s at the origin. Its speed is reduced to 1.46 * 10^5 m/s at the point x = 2.00 cm. Calculate the electric potential difference between the origin and that point.

physics
A proton is projected in the positive x direction into a region of uniform electric field E = (-6.80 * 10^5 N/C at t = 0. The proton travels 6.80 cm as it comes to rest. (a) Determine the acceleration of the proton. thanks

physics
A proton moves at 3.60 *10^5 m/s in the horizontal direction. It enters a uniform vertical electric field with a magnitude of 8.20* 10^3 N/C. Find the time interval required for the proton to travel 4.00 cm horizontally. thanks