Wednesday

May 25, 2016
Total # Posts: 1,830

**biochemistry**

the answer is 50 g w/v = 50g/500 ml = 10%
*February 16, 2011*

**biochemistry**

answer is % (w/w) = 21g/(500ml x 1.12 g/ml) = 21/560 = 3.75%
*February 16, 2011*

**biochemistry**

17g/375ml = 0.453% (w/v)
*February 16, 2011*

**Chemistry**

You dilute 0.4 M salt to 0.13 M , this is a dilution factor of 3.077. Thus, to make 3 L of final solution, you need 3L/3.077 = 974 ml or 0.974 L
*February 16, 2011*

**Physics**

A glacier moves with a speed of 42 nm/s. How many years would it take for the glacier to move 0.78 km? Answer in units of yr.
*February 14, 2011*

**Physics**

A glacier moves with a speed of 42 nm/s. How many years would it take for the glacier to move 0.78 km? Answer in units of yr.
*February 14, 2011*

**Physics**

A glacier moves with a speed of 42 nm/s. How many years would it take for the glacier to move 0.78 km? Answer in units of yr.
*February 14, 2011*

**math **

i am sorry ms.sue i just changed because i ashamed that i always posted question on my homework and i afraid that anyone might not help my homework because of keep on posting but i really thanks to you and i hope you will help me to solve the problem i posted thanks and ...
*February 13, 2011*

**math**

hi to all teachers kindly please help me to solve this word problems thanks and god bless u always.question is below.i need for my homeworkpls. q.Saltly has a piece of cloth. She used 1/3 of the cloth to make a pillow cover and another 4/7 of the cloth to make a tablecloth. a...
*February 13, 2011*

**PHYSICS PLEASE HELP**

An astronaut in his space suit and with a propulsion unit (empty of its gas propellant) strapped to his back has a mass of 134 kg. During a space-walk, the unit, which has been completely filled with propellant gas, ejects some gas with a velocity of +32 m/s. As a result, the ...
*February 9, 2011*

**Shurley English**

warm hot cold
*February 8, 2011*

**Economics**

the price of labor is $100 per unit and the price of capital is $20 per unit. What will the long-run total cost and long-run average cost of producing 120 units?
*February 6, 2011*

**science**

The engines of a 1.20 x 10^5 N rocket exert an upward thrust of 2.00 x 10^5 N for 1.50 minutes upon lift off. What is the impulse exerted on the rocket? What is the velocity of the rocket at the end of the 1.50 minute period?
*February 3, 2011*

**Earth Science**

a very fast car hits a stationary(staic) truck.
*February 2, 2011*

**music**

Write a 4 bar piano piece in d harmonic minor. Use full cadence.
*February 2, 2011*

**music**

Write a 4 bar piece in e harmonic minor. Use and label one diminished triad. Copy the melody into six other clefs.
*February 2, 2011*

**Texas High**

The republicans traded the presidency in exchange for railroad monopolies
*February 2, 2011*

**Music**

well there was the gregorian chant ...... thats all i noe.. srry
*February 2, 2011*

**FP/101**

Some individuals prefer to have their employers withhold more money than they will owe so they can get big refund checks in April or May. Others prefer to minimize withholdings, so they can either spend the money throughout the year, or put it into a retirement or other ...
*February 2, 2011*

**physics**

A 5.50 104 kg space probe is traveling at a speed of 11000 m/s through deep space. Retrorockets are fired along the line of motion to reduce the probe's speed. The retrorockets generate a force of 4.00 105 N over a distance of 2600 km. What is the final speed of the probe?
*January 26, 2011*

**math**

niran has 72 centimeters of molding to make a frame for a print. this is not enough molding to frame the entire print.How shouldhe cut the molding to give the largest possible area for the print using the inside edge of the molding as the perimeter?
*January 26, 2011*

**physics HELP**

A 7450 kg satellite has an elliptical orbit, as in Figure 6.9b. The point on the orbit that is farthest from the earth is called the apogee and is at the far right side of the drawing. The point on the orbit that is closest to the earth is called the perigee and is at the far...
*January 26, 2011*

**physics help!!**

it doesn't give me the time...
*January 26, 2011*

**physics help!!**

A 5.50 104 kg space probe is traveling at a speed of 11000 m/s through deep space. Retrorockets are fired along the line of motion to reduce the probe's speed. The retrorockets generate a force of 4.00 105 N over a distance of 2600 km. What is the final speed of the probe?
*January 26, 2011*

**physics**

at it's peak the speed is zero, and the only acceleration is toward gravity, -9.81m/s^2
*January 25, 2011*

**physics HELP**

A 60.0 kg skier rides a 2740 m long lift to the top of a mountain. The lift makes an angle of 14.7¡ã with the horizontal. What is the change in the skier's gravitational potential energy?
*January 25, 2011*

**Algebra 2**

reciprocal is number that when times together gets u 1. so 1/-0.01=-100 and 1/2.34=.427...
*January 25, 2011*

**cal**

let s(t)= -16t^2 + 50 represent the distance in ft. from the ground of an object t seconds after initial velocity of the object? initial means t=0 1. what is the initial velocity of the object? 2. what is the velocity of the object 1 sec after it was released? 3. when does the...
*January 23, 2011*

**chemistry**

Light bulbs emit a broad spectrum of light; that is, they emit photons with a broad range of wavelengths. Suppose that 10% of the photons from a 75-Watt (on watt is one joule per second) bulb are emitted with an average wavelength of 500 nm (middle of the green rage, where our...
*January 22, 2011*

**chemistry**

(a) The characteristic emission from Ca occurs at 422.7 nm and corresponds to an electron going from a 4p orbital to a 4s orbital. Calculate the energy of the electron in the 4p orbital. Calculate Zeff for the electron in the 4p orbital. (b) The same 4p to 4s transition in ...
*January 22, 2011*

**chemistry**

Hydrogen-like ions are those with only one electron such as He+ and Li2+. The Balmer formula for the transitions in these ions can be written as v=Z^2 cR(1/(n_1^2 )-1/(n_2^2 )). Use this formula to calculate the lowest-energy transition in the Lyman and Balmer series for He+ ...
*January 22, 2011*

**chemistry**

Suppose a sample of hydrogen gas is excited to the n=5 level. As the atoms return to the ground state (Balmer series), they emit light. a. How many lines are there in the spectrum? b. Draw an energy-level diagram indicating theses transitions. c. Calculate the three lowest-...
*January 22, 2011*

**chemistry**

Calculate the energy (in eV) of the three lowest energy transitions in the Lyman series (the series that ends on n=1) of hydrogen. The wavelengths of these transitions are 121.6 nm, 102.6nm, and 97.3 nm. Draw an energy level diagram of these transitions
*January 22, 2011*

**chemistry**

A tube containing hydrogen atoms in the n=3 shell does not absorb visible light. The longest wavelength absorbed is 1875 nm. What state is the hydrogen atom in after absorbing a 1875 nm photon?
*January 22, 2011*

**chemistry**

We encounter a large number of waves every day without realizing it. One such source is radio waves. A typical frequency for radio transmission is 680 kHz. How much energy does one mole of radio waves carry? X rays used by doctors to view bones are much more energetic than ...
*January 22, 2011*

**chemistry**

Excited lithium atoms emit radiation at 670.8nm. a. calculate the frequency of this radiation. b. calculate the energy (in eV) of this radiation. c. What color is this radiation?
*January 22, 2011*

**chemistry**

Excited lithium atoms emit radiation at 670.8nm. a. calculate the frequency of this radiation. b. calculate the energy (in eV) of this radiation. c. What color is this radiation?
*January 22, 2011*

**College algebra**

simplify by removing factors of 1 n^2-9/(n+3)^2
*January 21, 2011*

**chemistry**

Copper reacts with sulfuric acid according to the following equation: 2H3SO4 + Cu-> CuSO4 + 2H2O + SO2 How many grams of sulfur dioxide are created by this reaction if 14.2 g of copper reacts with 18 g of sulfuric acid?
*January 20, 2011*

**chemistry**

Ammonia gas can be prepared by the reaction CaO(s) + 2NH4Cl(s) -> 2NH3(g) + H2O(g) + CaCl2(s) If 112 g CaO reacts with 224 g NH4Cl, how many moles of reactants and products are there when the reaction is complete?
*January 20, 2011*

**chemistry**

Copper reacts with sulfuric acid according to the following equation: 2H3SO4 + Cu-> CuSO4 + 2H2O + SO2 How many grams of sulfur dioxide are created by this reaction if 14.2 g of copper reacts with 18 g of sulfuric acid?
*January 20, 2011*

**chemistry**

Ammonia gas can be prepared by the reaction CaO(s) + 2NH4Cl(s) -> 2NH3(g) + H2O(g) + CaCl2(s) If 112 g CaO reacts with 224 g NH4Cl, how many moles of reactants and products are there when the reaction is complete?
*January 20, 2011*

**chemistry**

determine the value of x for the following reaction: 4C + S8-> 4CS2 3.2 mol S8 yield x mol CS2
*January 20, 2011*

**chemistry**

How many moles of oxygen can be obtained by the decomposition of 7.5 mol of reactant in the following reaction? 2KClO3 -> 2KCl + 3O2
*January 19, 2011*

**math**

y=2x-5 shifted down one
*January 19, 2011*

**math**

how do you change a linear equation to make the graph steeper?
*January 19, 2011*

**chemistry**

How many moles of gas does it take to occupy 120 L at a pressure of 233 kPa and a temperature of 340 K?
*January 18, 2011*

**chemistry**

The solubility of NaCl in water is 35.7 g NaCl/100 g H2O. Suppose that you have 500.0 g of NaCl. What is the minimum volume of water you would need to dissolve it all? The density of water is 1.0 g/mL.
*January 17, 2011*

**chemistry**

An explosive whose chemical formula is C3H6N6O6 produces water, carbon dioxide, and nitrogen gas when detonated in oxygen. write the chemical equation for the detonation reaction of this explosive.
*January 17, 2011*

**chemistry**

which is the symbol for the following monatomic ion? 8 protons and 10 electrons
*January 17, 2011*

**chemistry**

On average, earth's crust contains about 8.1% aluminum by mass. If a standard 12-ounce soft drink can contains approximately 15.0g of aluminum, how many cans could be made from one ton of the Earth's crust?
*January 17, 2011*

**chemistry**

Titanium is used in airplane bodies because it is strong and light. It has a density of 4.55 g/cm^3. If a cylinder of titanium is 7.75 cm long and has a mass of 153.2 g, calculate the diameter of the cylinder. (V=pi*r^2*h, where V is the volume of the cylinder, r is the radius...
*January 17, 2011*

**chemistry**

Mercury has a density of 13.6 g/mL. What is the mass of 4.72 L of mercury?
*January 17, 2011*

**chemistry**

Mercury has a density of 13.6 g/mL. What is the mass of 4.72 L of mercury?
*January 17, 2011*

**chemistry**

Mercury has a density of 13.6 g/mL. What is the mas of 4.72 L of mercury?
*January 17, 2011*

**chemistry**

A sample of crude oil has a density of 0.87g/mL. What volume in liters does a 3.6-kg sample of this oil occupy?
*January 17, 2011*

**chemistry**

No! It Al(OH) with the subindex of 2 ==> Al to the power+ plus OH with a negative sign on the top!
*January 15, 2011*

**chemistry**

balance the chemical equation: Al(OH)2-- Al^2+ +OH^-
*January 15, 2011*

**chemistry**

show that 1mg/L = 1g/m3
*January 15, 2011*

**chemistry**

you made up a standard solution of calcium sulfate (CaSO4). the temperature is 25C. you then add 5.00*10^-3 odium sulfate (Na2SO4). Calculate the concentrations of calcium and sulfate after equilibrium is reached? The pKs of CaSO4 is 4.58.
*January 15, 2011*

**chemistry**

The concentration of a chemical degrades in water according to order kinetics. the degradation constant is 0.2 day^-1. if the initial concentration is 100.0 mg/L, how many days are required for the concentration to reach 0.14 mg/L?
*January 15, 2011*

**chemistry**

the concentration of a chemical degrades in water according to order kinetics. the degradation constant is 0.2 day^-1. if the initial concentration is 100.0 mg/L, how may days are required for the concentration to reach 0.14 mg/L?
*January 15, 2011*

**chemistry**

if 200mg of HCl is added to water to achieve a final volume of 1.00 L, what is the final pH?
*January 15, 2011*

**chemistry**

a) 45.00g/L(1000mg/g)(1L/1000mL)=45mg/mL b)NaHCO3: 22.99+1+12+3(16)= 83.99g/mol prop. of Na (22.99/83.99)=0.54 c)? d)?
*January 15, 2011*

**chemistry**

A solution of sodium bicarbonate is prepared by adding 45.00g of sodium bicarbonate to a 1.00-L volumetric flask and adding distilled water until it reaches the 1.00-L mark. Calculate the concentration of sodium in units of: a) milligrams per liter b) molarity c) normality d) ...
*January 15, 2011*

**Chemistry**

A solution is made by dissolving 10.20 grams of glucose (C6H12O6) in 355 grams of water. What is the freezing-point depression of the solvent if the freezing point constant is -1.86 °C/m?
*January 14, 2011*

**engineering**

If faucet is dripping at a rate of one drop per second and each drop contains 0.150 milliliters. Calculate how much water will be lost in 1 year.
*January 14, 2011*

**World History**

How was the grenade developed to help the war effort?
*January 13, 2011*

**PHI.: 103**

what fallacy is this? I don't know what colleges are teaching these days! I have just received a letter of application from a young man who graduated from the state university last June. It was a wretched letter – badly written, with elementary errors in spelling, ...
*January 13, 2011*

**9th grade alegbra**

input/output numbers. i need the relation. x-1 2 3 4 5 y-0 5 28 81 176
*January 11, 2011*

**statistics**

from a group of six people two individuals are to be selected at random. How many possible selections are there?
*January 8, 2011*

**Statistics**

About how many participants are needed for 80% power in each of the following planned studies that will use a t test for dependent means with p < .05? Predicted Effect Size Tails (a) Medium Two (b) Large One (c) Small One
*January 8, 2011*

**Statistics**

About how many participants are needed for 80% power in each of the following planned studies that will use a t test for dependent means with p < .05? Predicted Effect Size Tails (a) Medium Two (b) Large One (c) Small One
*January 8, 2011*

**Math**

if a triangle has a perimeter of 50cm one side is double the length of the base and the second side is four less than three times the base how long is the base?
*January 6, 2011*

**Algrebra**

3u-ux/x=6y/x
*January 6, 2011*

**Math (algebra)**

(y-1)/2u+x=m what does "u" equal?
*January 6, 2011*

**Math (algebra)**

(x-u)/3=5-y what does "u" equal?
*January 6, 2011*

**math**

To multiply 5 by 3, you can find the product of 2 and 5 and the product of 1 and 5 and ________them.
*January 6, 2011*

**math**

Write 6+6+6+6=24 as a multiplication sentence.
*January 6, 2011*

**Science**

Can you answer my question please becaise I can not find my answer
*January 3, 2011*

**Math**

Alright thanks I get it now (: I guess I was just multiplying wrong.
*January 2, 2011*

**Math**

I don't get page 50 of algebra with pizzazz! Please help? 7) Kathy is 6 years younger than bill. 12 years ago bill was twice as old as Kathy was then. How old are they now?
*January 2, 2011*

**unscramble spanish words**

sandia
*January 2, 2011*

**Garland High school**

Suppose you must maintain a balance of least $500 in your checking account in order to have free checking. The current balance in your checking account is $635.27. Which inequality describes how much can write a check for a and still have free checking? A. 635.27>500-x B. ...
*December 30, 2010*

**physics**

phuthy sawal nae andy
*December 29, 2010*

**math**

(28-2 x9) with the power of 2 + 2x7
*December 27, 2010*

**Algebra**

How do I find the value of x such that the data set has the given mean. Example: 11,12,5,3,x; Mean=7.4
*December 14, 2010*

**soc 120**

1. The average height of members of the high scho etball team is six feet, three inches. Jerry is on the high school basketball team, so Jerry must be taller than six feet. The argument above is flawed because it confuses (Points : 1) Jerry with other members of the team the ...
*December 12, 2010*

**Comm**

Personal finance classes can help you if you have difficulties making budgets. Looking for verb and verb tense
*December 11, 2010*

**physics**

How much heat must be added to 0.55 kg of aluminum to change it from a solid at 180°C to a liquid at 660°C (its melting point)? The latent heat of fusion for aluminum is 4.0x10^5 J/kg. I understand the Equation Q=mc times change it T would that be .55 times 4.0 x 10^5 ...
*December 10, 2010*

**physics**

im wondering the same thing as leah cause i left mass in kg and it was marked wrong please help
*December 10, 2010*

**physics**

How much heat must be added to 0.55 kg of aluminum to change it from a solid at 180°C to a liquid at 660°C (its melting point)? The latent heat of fusion for aluminum is 4.0 105 J/kg.
*December 10, 2010*

**4th grade**

Jorge and Hector like to play marbles.Jorge had 7 more than four times the number of marbles that Hector had. Together they had 37 marbles. How many marbles did Jorge have?
*December 9, 2010*

**algebra**

(1-2i)(1+2i)
*December 7, 2010*

**Chemistry**

why do isomers have different properties? please give examples.
*December 7, 2010*

**physics**

Two identical containers are open at the top and are connected at the bottom via a tube of negligible volume and a valve which is closed. Both containers are filled initially to the same height of 1.00 m, one with water, the other with mercury, as the drawing indicates. The ...
*December 6, 2010*

**trigonometry**

find all degrees solutions to the following equation: sin (A + 50 degrees)=1/square root 2
*December 5, 2010*

**physics**

the negative charge distribution over the surface of two isolated spheres is depicted in the diagram. one of the spheres is made of copper and the other is of rubber. identify the sphere that depicts the charge distribution of copper and that of rubber. support the answer with...
*December 1, 2010*

**physics**

a positively charged light metal ball is suspended between two oppositely charged metal plates on an insulating thread. after being charged once. the plates are disconnected from the battery. describe the behavior of the ball. (the plates are not touching nothing and the ball ...
*December 1, 2010*