Friday

April 18, 2014

April 18, 2014

Total # Posts: 147

**math**

What would you do first to order the following numbers from least to greatest? 30%, 2/3, 0.67, 8/9, 0.7

**Chemistry**

In the equation N2 + 2 O2 → 2 NO2, 14 g of nitrogen can produce how many grams of nitrogen dioxide?

**Buisness Math**

You are interested in purchasing a wide-screen television set at Target. On this type of TV, the ratio of screen width to screen height is 16 to 9. If a certain model you are considering has a screen width of 48 inches, what is the height of the screen (in inches)? (Points : 2)

**Physical Science**

what will have a greater effect on the intensity of a sound, doubling its power or halving its distance? Explain your answer.

**Physics**

A 3.0kg object originally at rest explodes and splits into three fragments. One fragment has a mass of .50kg and flies off along the negative x-axis at a speed of 2.8m/s, and another has a mass of 1.3kg and flies off along the negative y-axis at a speed of 1.5m/s. What are the...

**Physics**

A 1560 kg car is traveling with a speed of 14.5 m/s. What is the magnitude of the horizontal net force that is required to bring the car to a halt in a distance of 53.3 m?

**Chemistry**

Given a C=O double bond, how do you determine the length of the bond in different molecules using resonance structures? I know single bonds are longer than double bonds...but how do you distinguish between lengths of the same double bond in different molecules?

**chemistry**

I posted this question last night but did not get an answer- I am posting again because I have an exam I am studying for and do not understand this concept! Thanks! Using the given data, and the table of Standard Reduction Potentials, find the standard reduction potential for ...

**chemistry**

Using the given data, and the table of Standard Reduction Potentials, find the standard reduction potential for this half reaction: 8H^+ + BaCrO4(s) + 3e- -> Ba^2+ + Cr^3+ + 4H2O(l) given: Ksp (BaCrO4)=2.1E-10 DeltaGf* (kJ/mol): CrO4^2- (-727.75), Cr2O7^2- (-1301.1), H+ (0)...

**chemistry**

Glutamate (Glu–) is the conjugate base form of glutamic acid (HGlu). The Ka of glutamic acid is 5.012 x 10^–5. You titrate 50 mL of 0.10 M sodium glutamate solution with 0.05 M HCl solution. Calculate the pH of the solution at the equivalence point. Ive been trying t...

**chemistry**

The Ksp for calcium fluoride (CaF2) is 3.9 x 10^–11 at 25°C. How many moles of solid NaF must be added to 1.00 L of 0.100 M CaCl2 in order to precipitate CaF2? Please help me set up this ICE table and understand how to solve this!! thank you!!

**chemistry**

You have .1 moles of H3PO4 in a soln with a total volume of 250 mL. You then add .15 moles of NaOH and dilute the soln to a total volume of 1L calculate the pH of the resulting soln and the concentrations of all aqueous species. Thanks!!!!

**chemistry**

Sorry- I forgot to add that the last value, (X-.31X) is raised to the 1/2 power

**chemistry**

For the equation, SO2(g) + 1/2 O2(g)-> SO3(g) Kp=9.5 EQUAL partial pressures of SO2 and O2 are placed in an empty reaction vessel and heated to 600 degrees celsius. Assuming that 62% of the SO2 partial pressure has reacting to give S03, calculate the partial pressure of S03...

**chemistry**

The normal boiling point of ethanol is 78.5C. Using the following information: delta H formation (C2H5OH (g))= -234.38 kJ/mol determine the enthalpy of vaporization of ethanol. I know it should be around 39.3 according to a table in my textbook, however, I don't know how t...

**chemistry**

Given: Ti=298K V=.005 L Pt=1 atm P H20 vapor= .0313atm P air= .9687 atm you increase the temperature to 338K; the total pressure remains 1 atm, but the volume increases. Determine the volume at the new temperature (assume water vapor reaches equilibrium at 338K) PLEASE help!! ...

**Chemistry**

A 1.00 L vessel contains 5 g N2 and 1.5 g H2O at 25 degrees C. Calculate the mass of LIQUID water that would be present in the vessel.

**algebra**

Solve the following equation or inequality for the unknown variable. Round answer to two decimal places if necessary.5n + 2 = 27 n=

**math**

A box contains 25 slips of paper, numbered 1 to 25. What is the probability that one will randomly select a number that is divisible by 3 or 7?

**trig**

Use a table of trigonometric values to find the angle è in the right triangle in the following problem. Round to the nearest degree, if necessary. cos è =0.9659 A=? H=20

**chemistry **

25.0 mL tap water is titrated with 0.00500 M EDTA 7.95mL EDTA is required for complete reaction with water hardness what is the molarity of the total water hardness

**chemistry**

A helium-ﬁlled balloon has a volume of 2.83 L at 30 ◦ C. The volume of the balloon decreases to 2.35 L after it is placed outside on a cold day. What is the outside temperature in K? Answer in units of K?

**Geography**

What's one issue that affects the workplace and how it is a problem that creates discussion among people with different points of view?

**Physics - Check my work please :)**

Check this please :D Which of the following three statements used to describe work are true: i)Work is done only if an object moves through a distance ii)Work is done only if energy is transferred from one form to another iii)Work is done only if a force is applied In which of...

**Physics :D**

An electric motor is tested and found 76% efficient. if the input work is 400 J, what is the motors output work? A ramp has a length of 4m and a height of 1.5m. If a man pushes a 40N crate to the top of the ramp with a force of 60N, what is the efficiency of the ramp? How do I...

**Impacts**

How does the health care system affect our society socially, economically and environmentally?

**chemistry (please help)**

How many liters of .0020 M iodine solution can be made from .050 moles of iodine (I2)?

**Physics**

A 85.0 N weight is held in the hand. The upper arm makes an angle of 32.0° with the vertical, and the lower arm is 10.0° above the horizontal. Find the tension in the biceps tendon. See figure below.

**Physics**

where is the 1.91 coming from?

**Physics**

I know that the angular acc is g/d or 9.8/2.14=4.58 rad/s^2

**Physics**

A child sits down on one end of a horizontal seesaw of negligible weight, 2.14 m from the pivot point. No one balances on the other side. Find the instantaneous angular acceleration of the see-saw and the tangential linear acceleration of the child.

**Physics**

An amusement park ride called the Rotor consists of a room in the shape of a vertical cylinder (2.10 m in radius) which, once the riders are inside, begins to rotate, forcing them to the wall. When the room reaches a speed of one rotation every 1.36 s, the floor suddenly drops...

**physics**

Compute the orbital radius of an earth satellite that has an equatorial orbit and always remains above a fixed point P on the earth's surface. Communication satellites have such "geosynchronous" orbits (see figure). These satellites are used to relay radio and te...

**Physics**

A particle with an initial linear momentum of 2.28 kg · m/s directed along the positive x-axis collides with a second particle, which has an initial linear momentum of 4.56 kg · m/s, directed along the positive y-axis. The final momentum of the first particle is ...

**physics**

A bowling ball weighing 40.0 N initially moves at a speed of 4.90 m/s. How long must a force of 54.0 N be applied to the ball to stop it?

**Physics**

A boy of mass 49.4 kg is initially on a skateboard of mass 2.00 kg, moving at a speed of 10.3 m/s. The boy falls off the skateboard, and his center of mass moves forward at a speed of 10.9 m/s. Find the final velocity of the skateboard.

**Physics**

thanks! I'm studying for a test and this helps me tremendously!

**Physics**

Find the linear momentum and kinetic energy of a bullet of mass 4.80e-2 kg moving at a speed of 320 m/s. I found the linear momentum to be 15.36 by doing m*v but I can't figure out the kinetic energy.

**physics**

A rubber ball of mass 18.0 g is dropped from a height of 1.75 m onto a floor. The velocity of the ball is reversed by the collision with the floor, and the ball rebounds to a height of 1.55 m. What impulse was applied to the ball during the collision?

**Physics**

Yea, I was wondering the same thing because mine is wrong too!

**Physics**

A 1.21 kg block slides down a 25.0 m long 25.0° incline at constant velocity. How much work is done by friction?

**physics**

Ten boxes, each 16.0 cm high and weighing 250 N, initially are all side by side on the floor. The boxes are lifted and placed in a vertical stack 1.60 m high in a time interval of 7.00 s. Compute the power necessary to stack the boxes.

**College Physics**

I feel like the acceleration isn't correct.

**College Physics**

I worked out the first equation for part a and found the acceleration to be -0.2304. When doing the second equation, I found work to be -8478.72 J. Can work be negative? I feel like I haven't worked this out correctly.

**Physics**

Thanks so much!

**Physics**

A man of mass 75.5 kg walks down the aisle of an airplane at a speed of 1.50 m/s in the forward direction while the plane moves at a speed of 305 m/s relative to the earth. (a) Find the man's kinetic energy relative to the plane. (b) Find the man's kinetic energy relat...

**Physics**

A hovercraft of mass 77.0 kg can move on a horizontal surface, the x-y plane. A single unbalanced force acts on the hovercraft, but the size of the force is unknown. The hovercraft initially has a velocity of 6.0 m/s in the positive x direction and some time later has a veloci...

**physics**

Suppose you carry a bag of groceries weighing 127 N from your car to your kitchen, a distance of 48 m, without raising or lowering the bag. (a) What is the work done by the force you exert on the bag?

**Please help!!!!!Physics**

Find the resultant force on (a) the mass m1 = 0.183 kg and (b) the mass m2 = 0.106 kg (the masses are isolated from the earth).. The first mass is 400kg and its 10 cm from the second mass which is 0.183 kg (m1). the second mass is 10 cm away from the third mass which is 0.106 ...

**Physics**

John weighs 660 N, and Marcia weighs 486 N. Estimate the gravitational force between them when they are 0.47 m apart. I've tried finding the mass of john and marcia by doing m=F*a (F being their weight in Newtons and a being 9.8 m/s^2). When I found their masses, I applied...

**word problem**

45 is the only thing it could be.

**physics**

(2.8 miles/41 Seconds) x (60 seconds/1 minute) x (60 minutes/ 1 hour) = 245.85 mph (or miles per hour)

**Math**

c=0.2887

**animals**

take it outside constantly. while outside, when the puppy does its business give her a treat. when your inside and the puppy does it's business (say on the kitchen floor), then point to the puppy and say NO! with force. you don't have to hit it or even touch it. Just l...

**College physics (simple)**

what exactly does mu stand for?

**College physics (simple)**

Two blocks (one on top of the other), each of mass m = 2.4 kg, are pushed along the horizontal surface of a table by a horizontal force P of magnitude 6.8 N, directed to the right. The blocks move together to the right at constant velocity. (a) Find the frictional force exerte...

**College physics (simple)**

Two blocks (one on top of the other), each of mass m = 2.4 kg, are pushed along the horizontal surface of a table by a horizontal force P of magnitude 6.8 N, directed to the right. The blocks move together to the right at constant velocity. (a) Find the frictional force exerte...

**Physics**

Two blocks (on top of one another), each of mass m = 2.4 kg, are pushed along the horizontal surface of a table by a horizontal force of magnitude 6.8 N, directed to the right. The blocks move together to the right at constant velocity. (a) Find the frictional force exerted on...

**math**

what is (x to the 3rd power + x to the 2nd power) divided by ((x+4)(X-4)) multiplied by (x+4) divided by (3x to the 4th power + x to the 3rd power + 2x to the 2nd power)

**early childhood education**

B is right

**Media & american culture**

I need help with a thesis sentence about music stating how & why it is more than an important piece of entertainment

**child care**

thank you very much

**child care**

windows of time during which enviorment influences on development are enhanced are called blank periods? a.sensitive b. critical c. crucial d. necessary i say c?

**math**

how do you find ...weekly sales in thousands of items of a product has a seasonal sales record approximated by y=18.1sin(piex/24)+52.9 where x is time in weeks and 1 is the first week in janurary. during which weeks will the sales equal 61,950 items this year? list all the wee...

**geometry**

A ship leaves port and heads due east at a rate of 32 miles per hour. Ever since the ship left port, it has been pushed south by a strong constant wind. Five hours after leaving port, the ship is 200 miles away. What is the effective push on the ship from the wind?

**biology**

Who discovered DNA was it James Watson and Francis Crick or Friedrich Miescher ? thankyou

**chem**

What would happen to the specific heat if some of the warm metal shot were lost during the transfer to the calorimeter? Answer a. It would not affect the calculated value of specific heat b. It would cause the calculated value of specific heat to be artificially high c. It wou...

**chemistry**

Calculate the change in internal energy for a system that absorbs 242 J of heat and does 193 J of work on the surroundings...

**Chemistry**

At what temperature (oC) will a gas sample occupy 6.1 L if it originally occupies 17.8 L at 27.1oC? I did (v1/t1)=(v2)/(t2) v1=17.8 v2=6.1 t1=27.1 C = 300.25 K the answer i got for t2= 102.894 K which would be -170.106 C This doesnt seem right is it?

**chemistry**

A balloon is filled with 2.3 cm3 helium gas at 112.1 atm pressure. What will be the new pressure (atm) if the volume is changed to 44.7 cm3? P1V1=P2V2 (112.1)(.0023)=(P2)(.0447) the answer i got was 54.85 so would the answer be 54.85 atm?

**chem**

A 16.5 cm3 bubble under the ocean at 2.1 atm and 12.5oC surfaces to 1.0 atm and 22.1oC. What is the new volume (in cm3)? i used (p1)(V1)/T1=(P2)(V2)/T2 (2.1)(.0165)/285.65=(1)(V2)/295.25 THE ANSWER I GOT IS .0335 i changed 16.5 to liters which is why its .0165 is this correct?

**college chem**

A balloon is filled with 2.3 cm3 helium gas at 112.1 atm pressure. What will be the new pressure (atm) if the volume is changed to 44.7 cm3? P1V1=P2V2 (112.1)(.0023)=(P2)(.0447) the answer i got was 54.85 so would the answer be 54.85 atm?

**drwls history**

please could i say a huge thankyou you have helped me alot and i appreciate it thankyou again you are a star! :]

**HISTORY**

please could someone help me answer this question why relations between britain and germany changed in the years 1936-1939? was it because britain didnt want to get involved with germany because they didnt want another war to start? im not sure what to write.

**chemistry **

Determine the density of methane (CH4) in g/L at 24.7oC and 1.1 atm ideal gas eqn: P = (rho)RT, where: pressure: P = 1.1 atm specific gas constant: R, R = |R / M, where |R = 0.0821 L-atm / K-mol and, molecular weightCH4: M = 0.016 kg/mol R = 0.0821/0.016 = 5.13 and temp. T = 2...

**chemistry**

A 16.5 cm3 bubble under the ocean at 2.1 atm and 12.5oC surfaces to 1.0 atm and 22.1oC. What is the new volume (in cm3)?

**chemistry**

At what temperature (oC) will a gas sample occupy 6.1 L if it originally occupies 17.8 L at 27.1oC?

**chemistry**

so (1)(.285)=(22.4)(273.15) what do I do next?

**chemistry**

A volume of 0.285 L of a gas at STP weighs 0.537 g. Calculate the molar mass of the gas.

**gcse french**

i need to write about what my future partner will be like i need to use future tense and negative tense any help id appreciate thankyou! :}

**chemistry**

a. How many atoms of hydrogen are in 25.0 g of ammonia (NH3)? Use the format 6.02E+23 for 6.02 x 10^23 b. How many atoms of nitrogen are in the same amount of ammonia I know to find the number of atoms in a gram of a sample you must multiply by 6.02*10^23. So i multiplied 25*6...

**chemistry**

Solid magnesium metal reacts with chlorine gas according to the following equation: Mg + Cl2 --> MgCl2 What mass of magnesium chloride is formed in the reaction between 7 g of Mg and 13.2 g of Cl2 I got 7/24.3= .288 13.2/70.90= 1.861777 thats as far as i got and im stuck an...

**chemistry**

what type of reaction is this Li + H2O --> LiOH A. Combination B. Combustion C. Decomposition Im thinking combination but the H2 is confusing me

**chemistry**

Solid magnesium metal reacts with chlorine gas according to the following equation: Mg + Cl2 --> MgCl2 What mass of magnesium chloride is formed in the reaction between 7 g of Mg and 13.2 g of Cl2 is this correct 7 g+13.2 g = 20.2 grams ?

**chemistry **

2C2H6(g) + 7O2(g) > 4CO2(g) + 6H2O(g) KCl(s) > K(s) + Cl2(g) is this balanced?

**chemistry**

a. How many atoms of hydrogen are in 25.0 g of ammonia (NH3)? Use the format 6.02E+23 for 6.02 x 1023 b. How many atoms of nitrogen are in the same amount of ammonia?

**chemistry**

Solid magnesium metal reacts with chlorine gas according to the following equation: Mg + Cl2 --> MgCl2 What mass of magnesium chloride is formed in the reaction between 7 g of Mg and 13.2 g of Cl2

**Language Arts**

What are 5 general elements or characteristics of the tall tale John Henry?

**math**

Place decimal points in these numbers so that their sum is 519.654. 329 913 477 624

**Math**

156

**chemistry**

When 25.0 g of Zn reacts, how many L of H2 gas are formed at 25 °C and a pressure of 854 mmHg?

**physics**

45^2=r^2/r^2....^2cancel's. Take the square root of 45*earths radius 6,380,000(in meters)=4.27x10^7

**Math**

Is my answer correct? The population of a city is 160,000 and is increasing at a rate of 1.5% each year. Approximately when will the population reach 320,000? My answer is approximately 46 years. Is that right? Thx

**o level economics**

Oops, I didn't think about medication. Can I list a job as a need? you need a job to earn money so i would think it's necessary for survival.

**o level economics**

We were asked to come up with a list of needs for ourselves, for our grandparents and for people our age in another continent. For my grandparents I have shelter from the war, warm blankets for winter. For someone my age in Africa I have money for school uniform and school fee...

**Maths (URGENT)**

FIND THE POSITION AND NATURE OF THE STATIONARY POINT ON THE CURVE Y = 3x^5 - 10x^3 +15x Can you find dy/dx and can you simplify it please.

**Algebra **

How do you know if a value is a solution for an inequality? How is this different from determining if a value is a solution to an euation? If you replace the equal sign of an equation with an inequality sign, is there ever a time when the same value will be a solution to both ...

**Math**

45% of the tree in a park are maple. There are 27 maple tree in the park. How many tree are there in all in the park?

**HELP PLEASE!!!**

CAN SOMEONE ANSWER I HAVE TO DO AN ESSAY ON THIS RIGHT NOW!!!!

**Spacecrafts**

I dunno thats why i asked the question!