Friday

October 9, 2015
Number of results: 51,523

**chemistry**

What is the root mean square speed of argon gas at 300 K? 1. 4.33 × 102 m/s 2. 1.37 × 101 m/s 3. 3.96 × 102 m/s 4. 4.30 × 101 m/s 5. 5.92 × 102 m/s
*May 1, 2015 by Anonymous*

**chemistry please help **

The FM band of radio waves are measured in megahertz (MHz), which are the numbers you see on the radio dial. Therefore, a radio station at 102.5 on the FM dial has a frequency of 102.5 MHz or 102,500,000 Hz. What is the wavelength of the radio station that has a frequency of ...
*October 31, 2010 by Tamina*

**algebra**

102 litre+0.01 m^3=? 102 liters is 102 * 10^-6 m^3 still confused x2+10=
*February 3, 2007 by Marcela*

**statistics**

It is known that the population mean for the Full Scale IQ of the WAIS is 100 with a standard deviation of 15. A researcher assesses a sample of 200 adults and find that they have a mean Full Scale IQ of 102. The point estimate of the mean for this group is ___________ and the...
*April 14, 2014 by Sally*

**statistics**

It is known that the population mean for the Full Scale IQ of the WAIS is 100 with a standard deviation of 15. A researcher assesses a sample of 200 adults and find that they have a mean Full Scale IQ of 102. The point estimate of the mean for this group is ___________ and the...
*April 15, 2014 by Katie*

**statistics**

It is known that the population mean for the Full Scale IQ of the WAIS is 100 with a standard deviation of 15. A researcher assesses a sample of 200 adults and find that they have a mean Full Scale IQ of 102. The point estimate of the mean for this group is ___________ and the...
*April 16, 2014 by Stacey*

**Chemistry**

If a system has 2.50 × 102 kcal of work done to it, and releases 5.00 × 102 kJ of heat into its surroundings, what is the change in internal energy of the system?
*November 11, 2011 by Harley*

**Chemistry**

what is the freezing point of an aqueous solution that boils at 102.1 C? Kf=1.86 Kb=0.512 102.1-100.0=2.1 2.1/0.512=4.10 4.10*1.86=7.62 C 7.62 C Is this correct?
*May 22, 2015 by lola*

**chemistry**

The following equation represents the partial combustion of methane, CH4. 2CH4(g) + 3O2(g) > 2CO(g) + 4H2O(g) At constant temperature and pressure, what is the maximum volume of carbon monoxide that can be obtained from 3.39 x 102 L of methane and 1.70 x 102 L of oxygen?
*October 4, 2014 by george*

**Chemistry**

A solution is made by mixing 5.00 × 102 mL of 0.167 M NaOH with 5.00 × 102 mL of 0.100 M CH3COOH. Calculate the equilibrium concentrations of H+, CH3COOH, CH3COO−, OH−, and Na+.
*March 20, 2015 by Sandhya*

**Math**

For the following data... 1. Provide evidence as to whether this data set if Gaussian or non Gaussian. 2. Determine the normal reference range. 3. Define a cut-off. Describe how a ROC curve can be used to determine such. 95 95 81 95 98 79 88 98 84 79 98 84 81 96 102 86 90 101 ...
*April 12, 2012 by Joe*

**Chemistry**

You have 4.271 x 102 mL of oxygen gas (O2) at 7.656 x 102 mm of Hg and 78 oC. What is the mass of the sample in milligrams? When alcohol evaporates according to the equationC2H5OH(l) --> C2H5OH(g), how many liters of gaseous alcohol, measured at STP, are created by the ...
*April 17, 2013 by Tif*

**Chemistry **

You have 4.271 x 102 mL of oxygen gas (O2) at 7.656 x 102 mm of Hg and 78 oC. What is the mass of the sample in milligrams? What is the ratio of effusion rates for a light gas, such as HF, to a heavy gas, such as UF4?
*April 16, 2013 by Tif*

**CHEMISTRY HELP !!!! **

Al3+ is reduced to Al(s) at an electrode. If a current of 2.75 ampere is passed for 36 hours, what mass of aluminum is deposited at the electrode? Assume 100% current efficiency. a. 9.2 x 10–3 g b. 3.3 x 101 g c. 9.9 x 101 g d. 1.0 x 102 g e. 3.0 x 102 g I think it is either B...
*May 7, 2014 by Anonymous*

**Physics**

A 1.0 102 g piece of copper at a temperature of 460 K and a 2.0 102 g piece of aluminum at a temperature of 2.2 102 K are dropped into an insulated bucket containing 5.0 102 g of water at 280 K. What is the equilibrium temperature of the mixture? (Use the specific heats found ...
*November 26, 2012 by Ray*

**chemistry**

A balloon is filled to a volume of 5.0 102 mL at a temperature of 28.0°C. The balloon is then cooled at constant pressure to a temperature of 1.00 102 K. What is the final volume of the balloon? the answer i got is v=166.66666667 My question is what is the correct sig. figures...
*April 29, 2010 by chase*

**Statistics**

98,99,99,103,101,102,104,89,87,90,90 Within how many standard deviations of the mean is the value 102?
*June 5, 2012 by Anonymous*

**Statistics**

87,89,90,90,98,99,99,101,102,103,104 Within how many standard deviations of the mean is the value 102?
*June 5, 2012 by Anonymous*

**chemistry**

The specific heat capacity of gold at 25°C is 1.290×10-1 J/g/K. For a 5.25×102 g sample of gold, how much will the temperature increase if 6.908×102 J of energy is put into the system? (Assume that the heat capacity is constant over this temperature range.)
*September 25, 2014 by korko*

**Chemistry**

A balloon is filled to a volume of 1.0 102 mL at a temperature of 38.0°C. The balloon is then cooled at constant pressure to a temperature of 1.00 multiplied by 102 K. What is the final volume of the balloon?
*June 11, 2010 by Brittney*

**chemistry**

A fuel mixture used in the early days of rocketry is composed of two liquids, hydrazine (N2H4) and dinitrogen tetraoxide (N2O4), which ignite on contact to form nitrogen gas and water vapor. 2 N2H4 + N2O4 --> 3 N2 + 6 H2O If 1.50 x 102 g of N2H4 and 2.00 x 102 g of N2O4 are...
*November 4, 2012 by Sheree'*

**AP Chemistry**

A balloon is filled to a volume of 2.0 102 mL at a temperature of 33.0°C. The balloon is then cooled at constant pressure to a temperature of 1.00 102 K. What is the final volume of the balloon?
*October 15, 2012 by Ashley*

**Math (check my work please?)**

A baseball player has 34 hits in 102 times at bat. Another baseball player has 24 hits in 96 times at bat. Write each player's batting average. Here's what I did: 34/102 = BP #1 24/96 = BP #2 34/102 = 1/3 24/96 = 1/4 1/3 --> 4/12 1/4 --> 3/12 4/12 + 3/12 = 7/12 7/12 ...
*October 16, 2013 by Teresa Perri*

**Math**

What is the cardinal number for the following sets? A) 101,102,103,104,.......121 B) (1,2), (101,102), (0,105)
*December 11, 2008 by Bria*

**Math**

What is the cardinal number for the follwing sets? 1). 101,102,103,104,....121 2). (1,2) (101,102) (0,105)
*December 11, 2008 by Bria*

**Chemistry**

Question: A sample of Freon-12 (CF2Cl2) occupies 2.261 x 101 L at 337 K and 2.917 x 102 kPa. Find its volume (in L) at standard temperature and pressure (STP). Equation: p1v1/t1=p2v2/t2 My Work: (2.917 x 102 kPa)(2.261x101 L)/337K = (101.3 kpa)( x )/273 k My Answer: 543.4 L Is...
*July 13, 2011 by Bradley*

**statistics**

98,99,99,103,101,102,104,89,87,90,90 Find the 25th and 75th percentiles. Within how many standard deviations of the mean is the value 102. Find the interquartile range.
*June 4, 2012 by Anonymous*

**Physics**

On the moon the surface temperature ranges from 395 K during the day to 1.02 x 102 K at night. Convert these temperatures to the Celsius and Fahrenheit scales. (a) 395 K in degrees Celsius; (b) 395 K in degrees Fahrenheit; (c) 1.02 x 102 K in degrees Celsius; (d) 1.02 x 102 K ...
*December 11, 2012 by Anonymous*

**Physics**

A hiker starts at his camp and moves the following distances while exploring his surroundings: 65.0 m north, 2.00 ✕ 102 m east, 1.10 ✕ 102 m at an angle 30.0° north of east, and 1.50 ✕ 102 m south. (a) Find his resultant displacement from camp. (Take east ...
*September 5, 2015 by Biggz*

**chem**

C2H4Br2 + 3 I- -> C2H4 + 2Br- + I3- [C2H4Br2]M [I1]M Initial Rate (M/s) 1 0.127 0.102 6.45 x 10-5 2 0.343 0.102 1.74 x 10-4 3 0.203 0.125 1.26 x 10-4 Determine the order of the reaction in C2H4Br2:
*February 4, 2007 by kim*

**CHEMISTRY HELP !!!! CHECK !!!**

Al3+ is reduced to Al(s) at an electrode. If a current of 2.75 ampere is passed for 36 hours, what mass of aluminum is deposited at the electrode? Assume 100% current efficiency. a. 9.2 x 10–3 g b. 3.3 x 101 g c. 9.9 x 101 g d. 1.0 x 102 g e. 3.0 x 102 g Answer 2.75 A for 36 ...
*May 8, 2014 by YULCHANG*

**chemistry**

At what temperature (in ) does acetone have = 102
*January 20, 2010 by aamani*

**Please help with steps: Geometry**

Two mountain bikers have been separated and are hoping to find each other. One biker reads on her GPS that she is located at 102.9 degrees west and 44.1 degrees north. She decides to ride towards the mountain peak, which on the map has the coordinates 102.5 degrees west and 44...
*November 2, 2011 by Erika*

**Chemistry**

What is the molarity of a 5.00 x 102 ml solution containing 2490 g of KI?
*August 18, 2013 by Victoria*

**Chemistry**

What is the energy and frequency of a photon with a wavelength of 2.57 ×102 m?
*April 17, 2015 by nona*

**Chemistry**

A sample of nitrogen gas is confined in a 8.494 L container at 2.643 x 102 torr and 50 oC. How many moles of gas are present in the sample? So I thought I set this problem up right and when I type the answer into CALM my answer is incorrect. This is what I did: PV=nRT (2.643 x...
*January 20, 2014 by Cassie*

**Chemistry**

What is the freezing point of an aqueous solution that boils at 102.1 C?
*April 26, 2010 by Justin*

**chemistry**

Determine the energy of a photon with a wavelength of 6.74 ✕ 102 nm.
*November 9, 2013 by aaliyah*

**CHEMISTRY**

I used 10mL of unknown NaCl-NaBr mixture titrate with 0.10M silver nitrate solution. 10.15mL of silver nitrate solution is used. the conc. of NaCl-NaBr mixture is 8g/dm3 I need to calculate the % composition of the NaCl-NaBr mixture. I used the following calculation steps but ...
*April 29, 2010 by albee*

**college chemistry**

.361 g of a non-volatile solute is dissolved in 160.0 g of water. The solute does not react with water nor dissociate in solution. Assume that the resulting solution displays ideal Raoult's law behaviour. At 90 oC the vapour pressure of the solution is 5.1701×102 torr. (The ...
*February 18, 2011 by silver*

**chemistry**

At what temperature (in degrees C) does acetone have Pvap= 102 mmHg?
*January 25, 2010 by Lauren*

**Chemistry**

Calculate the velocities of electrons with de Broglie wavelengths of 1.7 102 nm and 5.0 nm, respectively.
*November 13, 2010 by Anna*

**Chemistry**

What is the molarity of a 2.50 x 102 cm3 solution containing 560.0 g of C6H12O6?
*November 6, 2014 by Jojo*

**Chemistry**

How many grams of lithium nitrate, LiNO3, are required to prepare 3.00 × 102 mL of 2.00 × 10–1 M solution?
*May 12, 2010 by Chris*

**chemistry**

Calculate the mass of KI in grams required to prepare 7.00 multiplied by 102 mL of a 2.60 M solution
*October 12, 2010 by Anonymous*

**Chemistry**

A brownie contains 1.30 ×102 mg of sodium. What is this mass equivalent to it in units of grams?
*February 20, 2011 by Des*

**Chemistry**

Calculate the number of moles in these quantities. 1. 25.0 g KNO3 2. 5.4 x 102 g (NH4)2C2O4
*March 20, 2011 by Netta*

**Physics**

A 3.60 102-kg piano is being lifted at a steady speed from ground level straight up to an apartment 18.0 m above the ground. The crane that is doing the lifting produces a steady power of 4.00 102 W. How much time does it take to lift the piano?
*February 25, 2008 by Peter*

**college: physics**

A 4.00 102-kg piano is being lifted at a steady speed from ground level straight up to an apartment 16.0 m above the ground. The crane that is doing the lifting produces a steady power of 4.00 102 W. How much time does it take to lift the piano?
*October 12, 2009 by Anonymous*

**Chemistry-102**

what is the ph solution obtained by mixing 25.00 ml of 0.250 ml HCl and 25.00ml of 0.125M NaOH
*March 23, 2011 by Christian*

**Chemistry**

A 1-ounce serving of Cheetos has 2.90 ×102 mg of sodium. What is this mass equivalent to in units of grams?
*September 6, 2011 by Shelley*

**chemistry**

How many grams of lithium nitrate, LiNO3, are required to prepare 3.00 × 102 mL of 2.00 × 10−1 M solution?
*December 6, 2011 by kathy*

**chemistry**

For each of the following explain how you would prepare 1.0 L of a solution that is 0.10 M in K+. Repeat for concentrations of 1.0 × 102 ppm K+ and 1.0% w/v K+.
*September 12, 2012 by Anonymous*

**Geometry**

The following scores on the midterm exam in Chemistry 102 were recorded: 93 81 59 69 82 73 61 77 95 84 88 71 86 97 63 72 89 80 60 98 91 62 78 83 76 81 94 66 83 96 Find the interquartile range (IQR).
*November 22, 2009 by aleah*

**chemistry**

102.0 (typical frequency for FM radio broadcasting) Express your answer using four significant figures.
*December 8, 2011 by Anonymous*

**physics**

10. The following three point charges are placed on the x axis: +5.0 mC at x=0; +4.0 mC at x= -40 cm; and +6.0 mC at x= +80 cm. Find (a) the electric field magnitude and direction and (b) the electric potential at x= +10 cm. a) E = k(5E-6)/.102 +k(4E-6)/.502 - k(6E-6)/.702 = +...
*January 11, 2010 by tv*

**math**

A chemist has 30%, 40 % and 80 % acid solutions. All three were to be mixed to make 4.00 x 102 L of 38% acid solution but a mistake was made and the amounts of 30% and 80 % were reversed. The result was 4.00 X 102 L of 65 % acid solution. What were the amounts of each solution...
*November 17, 2012 by David*

**Math(Can someone please answer!!)**

ln [2.30E-2] = ln(0.102) - (k s-1)(2360 s) k = 6.31E-4 s -1 I did 2360k = 1n(0.102 * 0.023) 2360k = -6.055 then I divided 2360 by -6.055 but I didnt get 6.31e-4. Where did I mess up???
*March 11, 2012 by Hannah*

**MATH**

The following scores on the midterm exam in Chemistry 102 were recorded: 93 81 59 69 82 73 61 77 95 84 88 71 86 97 63 72 89 80 60 98 91 62 78 83 76 81 94 66 83 96 Find the interquartile range (IQR). I FORGET HOW TO DO THIS
*November 18, 2009 by JEN*

**math**

The following scores on the midterm exam in Chemistry 102 were recorded, 93 81 59 69 82 73 61 77 95 84 88 71 86 97 63 72 89 80 60 98 91 62 78 83 76 81 94 66 83 96 find the interquartile range. I do not understand this question.
*January 17, 2010 by Christy*

**chemistry**

What is the energy of a photon with a wavelength of 8.45 102 nm? (The speed of light in a vacuum is 2.998 108 m/s. Planck's constant is 6.626 10-34 J · s.)
*October 21, 2010 by mary*

**chem**

The molarity and the molality of a solution prepared by dissolving 2.00 g of ethanol C2H5OH with 100.0 g of water to give a final volume 102 mL are would i just add both the grams and divide by 102 for molarity? and molalty i would just add the mass?
*August 8, 2008 by so*

**Physics**

A certain CD has a playing time of 76 minutes. When the music starts, the CD is rotating at an angular speed of 4.8 102 revolutions per minute (rpm). At the end of the music, the CD is rotating at 2.1 102 rpm. Find the magnitude of the average angular acceleration of the CD. ...
*March 24, 2008 by John*

**physivs**

A certain CD has a playing time of 68 minutes. When the music starts, the CD is rotating at an angular speed of 4.8 102 revolutions per minute (rpm). At the end of the music, the CD is rotating at 2.1 102 rpm. Find the magnitude of the average angular acceleration of the CD. ...
*December 4, 2010 by Anonymous*

**chemistry**

i need to know if I am in the right tract please let me know...I am calulating the molality of the following exercise so I could be able to apply the formula T=Kf * molality calculate the freezing point of a solution containin 12.2 grams of benzoic acid, dissolved in 250 grams...
*October 27, 2008 by Joshua*

**chemistry**

I need to determine how many grams of Cesium Iodide following solutes would be needed to make 5.00 102 mL of a 0.300 M solution.
*October 1, 2012 by Shawn*

**physics**

A ship maneuvers to within 2.47×103 m of an island’s 1.76 × 103 m high mountain peak and fires a projectile at an enemy ship 6.13 × 102 m on the other side of the peak, as illustrated. The ship shoots the projectile with an initial velocity of 2.54×102 m/s at an angle of 72.6...
*December 6, 2014 by sis*

**physics**

A motorcycle (mass of cycle plus rider = 3.0 102 kg) is traveling at a steady speed of 20 m/s. The force of air resistance acting on the cycle and rider is 1.8 102 N. Find the power necessary to sustain this speed under the following conditions. (a) the road is level (b) the ...
*October 26, 2010 by joshua*

**physics**

A car with a mass of 1.2 × 103 kilograms starts from rest and attains a speed of 20 meters/second in 5 seconds. What net force acted on the car to cause that acceleration? 3.0 × 102 newtons 6.0 × 102 newtons 1.2 × 103 newtons 4.8 × 103 newtons 1.2 × 104 newtons
*June 22, 2015 by sc*

**college chem**

The cation M2+ reacts with NH3 to form a series of complex ions as follows: M2+ + NH3 M(NH3)2+ K1 = 102 M(NH3)2+ + NH3 M(NH3)2 2+ K2 = 103 M(NH3)2 2+ + NH3 M(NH3)3 2+ K3 = 102 A 1.0 × 10–3 mol sample of M(NO3)2 is added to 1.0 L of 15.0 M NH3 (Kb = 1.8 × 10–5). What is the ...
*April 24, 2011 by richard *

**physics**

A cheetah runs a distance of 102 m at a speed of 27 m/s and then runs another 102 m in the same direction at a speed of 34 m/s. What is the cheetah's average speed?
*September 18, 2010 by john*

**chemistry**

A kitten's normal body temperature is 102ºF. Express this temperature in ºC.
*January 31, 2012 by kr*

**Chemistry**

The boiling point of an aqueous solution is 102.35 °C. What is the freezing point? Constants can be found here.
*February 21, 2012 by Heather*

**Chemistry**

The boiling point of an aq solution 102.11 C. What is the freezing point?
*July 12, 2011 by Josh *

**chemistry**

Potassium perchlorate has a lattice energy of -599 kj/mol and a heat of hydration of -548 kj/mol. Find the heat of solution for potassium perchlorate when 10.6 g of potassium perchlorate is dissolved with enough water to make 102.7 ml of solution. (J-absorbed) find the ...
*September 18, 2009 by ella *

**Chemistry-102**

What is the pH obtained by mixing 50.00mL of 0.100N HOAc (acetic acid) and 25.00mL of 0.200N NaOH?
*March 27, 2011 by Christian*

**Chemistry**

The pressure of a 27o mL sample of gas is 102 kPa. What would be the pressure if the volume were increased to 378 mL?
*December 11, 2012 by Annaisabel*

**chemistry**

A sample of an ideal gas has a volume of 2.29 L at 2.90 × 102 K and 1.08 atm. Calculate the pressure when the volume is 1.57 L and the temperature is 302 K.
*May 7, 2013 by Alexis*

**chemistry**

How many grams of NaOH are contained in 5.0 × 102 mL of a 0.77 M sodium hydroxide solution? The molar mass of NaOH is 40.0 g/mol.
*October 15, 2014 by Dystinee*

**physics**

A car is moving at 53 miles per hour. The kinetic energy of that car is 5 × 105 J. How much energy does the same car have when it moves at 102 miles per hour? Answer in units of J HELP!!!! I've tried doing (5*10 J)* (102/53)^2 and I keep on getting it wrong PLEASE HELP ME ...
*December 14, 2014 by Edgar*

**CHEMISTRY**

The solubility of NaNO3 at 40 oC is 102 g/100 g H2O , what is the minimum amount of water to dissolve NaNO3 ( mass of solvent ) ?
*September 24, 2014 by MAD*

**Chemistry!**

a)consider the following reaction: Mg(s)+ 2HCl(aq) --> MgCl2 (aq)+H2 (g) What minimum amount of 1.75 M HCl is necessary to produce 27.5 L of H2 at STP? b) What is the freezing point of an aqueous solution that boils at 102.1 C?
*April 26, 2010 by Justin*

**algebra am i right**

Find the volume of a right circular cylinder whose base has an area of 6 cm^2 and whose height is 17 cm. [A] 153ð cm^3 [B] 612ð cm^3 [C] 102 cm^3 [D] 153ð cm^2 [E] None of these i think its C Please show your work. That's the right answer, but we'd like to know why too. um i ...
*September 27, 2006 by cassii*

**chemistry**

a liquid has an enthalpy of vaporization of 30.8 kg.mol. at 273 K it has a vapor pressure of 102 mmHg. What is the normal boiling point of this liquid
*February 17, 2011 by ella*

**chemistry**

a liquid has an enthalpy of vaporization of 30.8 kg.mol. at 273 K it has a vapor pressure of 102 mmHg. What is the normal boiling point of this liquid
*February 17, 2011 by ella*

**chemistry 1046**

Calculate the solubility (in grams per 1.00 102 mL of solution) of magnesium hydroxide in a solution buffered at pH = 9 the ksp of Mg(oh)2 = 2.06e-13
*July 3, 2012 by Anonymous*

**Chemistry**

A sample of carbon dioxide has a volume of 22.0 L at 5.80 x 102 mm Hg. What pressure, in torr, would be needed to increase the volume to 48.6 L at constant temperature?
*November 6, 2013 by Anonymous*

**chemistry**

A sample of carbon dioxide has a volume of 22.0 L at 5.80 x 102 mm Hg. What pressure, in torr, would be needed to increase the volume to 48.6 L at constant temperature?
*November 6, 2013 by Anonymous*

**Physics**

A baseball with a mass of 0.15 kilograms collides with a bat at a speed of 40 meters/second. The duration of the collision is 8.0 × 10-3 seconds. The ball moves off with a speed of 50 meters/second in the opposite direction. What is the value of the force? A. 1.8 × 102 newtons...
*March 15, 2013 by fredrick*

**Math for Educators**

Use Gauss's approach to find the following sums (do not use formulas). a. 1 + 2 + 3 + 4 +...+ 102 b. 1 + 3 + 5 + 7 +...+1001 a. The sum of the sequence is ? My answer 102-51(103)= 5,253 b. The sum of the sequence is? My answer 500.3(1,002)=501,300.6 Are my answers correct? If ...
*June 4, 2013 by Carol*

**Math**

Annie's math test scores are 68 82 82 88 92 98 Her median test score is.. A.30 B.82 C.85 D.88 C? The high temperature for the last 5 days were 28,28,32,55,77 What is the range? A.28 B.32 C.44 D.49 D? The high temperature for six days in August were 93,98,100,102,102,105 What ...
*March 21, 2013 by Jerald*

**Alpha decay**

Hi I am working on a question which discusses ununhexium atomic number 116 atom weight 292. This isotope undergoes 7 alpha decay reactions. I have calculated that after seven reactions the product would be 102 nobelium. I cannot understand how the atomic weight can be right...
*January 17, 2007 by Atom ant*

**chemistry**

a sample of water under study was found to boil at 102 degree celiceus at normal temperature and pressure . is the water pure
*June 23, 2011 by sanjeed*

**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?
*October 18, 2010 by kellie*

**chemistry quick homework help**

A sample of Freon-12 (CF2Cl2) occupies 2.507 x 101 L at 291 K and 2.518 x 102 kPa. Find its volume (in L) at standard temperature and pressure (STP).
*April 15, 2013 by will.i.am*

**Chemistry**

(a) A 102-g sample of water is placed in an insulated container and allowed to come to room temperature at 21°C. To heat the water sample to 41°C, how much heat must you add to it? kJ (b) Consider the hypothetical reaction, being run in an insulated container that contains 102...
*June 7, 2011 by Lance*

**physics**

A missile of mass 1.10 102 kg is fired from a plane of mass 5.50 103 kg initially moving at a speed of 3.15 102 m/s. If the speed of the missile relative to the plane is 1.06 103 m/s, what is the final velocity of the plane?
*November 29, 2012 by Anthony*

**physics**

A missile of mass 1.20 102 kg is fired from a plane of mass 5.50 103 kg initially moving at a speed of 3.05 102 m/s. If the speed of the missile relative to the plane is 1.21 103 m/s, what is the final velocity of the plane?
*March 14, 2014 by Anonymous*

**Rate of change problem**

In 1993, 90 houses were built. in 1997, 102 more houses were built. find the average rate of change in the number of new homes built. express the result in terms of new houses built per year. a. 1/3 b. 102/90 c. 3/1 d. 5/2 could you explain it too? i dont really get how to set...
*December 30, 2012 by kathy m.*

**Chemistry **

Determine the molarity (in mol/L) of NO2− ions in solution when 9.77×101 g of sodium nitrite is added to enough water to prepare 3.94×102 mL of the solution.
*March 2, 2011 by Colin*