# chelsea

Most popular questions and responses by chelsea-
## Chemistry

For the following chemical reaction... HCN (aq) + KOH (aq)----> H2O (l) + KCN (aq) write the net ionic equation, including the phases

*asked on October 4, 2013* -
## Chemistry

For the following, 2HBr (aq) + Ba(OH)2 (aq) ---> 2H2O (l) + BaBr2 (aq) write the net ionic equation including the phases

*asked on October 4, 2013* -
## Chemistry

H(f) Cl= 121.3 kj H(f) C= 716.7 H(f) CCl4= -95.7 calculate the average molar bond enthalpy of the carbon-chlorine bond in a CCl4 molecule. I have tried to figure it out and keep getting the wrong answer. Please help!

*asked on November 25, 2013* -
## chemsitry help again please

Write the formula of the conjugate base for acid HClO2 .

*asked on November 19, 2013* -
## physics

Reggie Jackson stepped up to the plate and hit a .15 kg fast ball traveling at 36m/s, the impact caused the ball to leave his bat with a velocity of 45 m/s in the opposite direction. If the impact lasted for .002 seconds, with what force did Jackson exert

*asked on May 27, 2009* -
## chemistry

If you add 5.0 mL of 0.50 M NaOH solution to 20.0 mL to Buffer C, what is the change in pH of the buffer? (where buffer C is 8.203 g sodium acetate with 100.0 mL of 1.0 M acetic acid) I have calculated the pH of buffer C to be 4.74. Now what? =\

*asked on November 7, 2010* -
## physics

A criminal is escaping across a rooftop and runs off the roof horizontally at a speed of 5.1 m/s, hoping to land on the roof of an adjacent building. Air resistance is negligible. The horizontal distance between the two buildings is D, and the roof of the

*asked on January 31, 2012* -
## math grade 8/ unit test lesson 13/unit 2

#12 the cones below are similar,although not drawn to scale.what is the radius of the larger cone. a)10 b)11 c)12 d)13 i think it is c

*asked on March 9, 2017* -
## Chemistry

Write the balanced neutralization reaction between H2SO4 and KOH in aq. solution. .350 L of .410 M H2SO4 is mixed with .300 L of .230 M KOH. What concentration of sulfuric acid remains after neutralization? ______ M H2SO4

*asked on October 4, 2013* -
## Calculus

Find expressions for the quadratic functions whose graphs are shown. One graph has the point (4,2) plotted in which the parabola passes through (U-shaped parabola- right side up) The vertex is at (3,0) and the parabola does not touch the y-axis for as much

*asked on September 21, 2010* -
## Chemistry

You purchased a 5.00 pound bag of sugar (sucrose, C12H22O11) at the grocery last week to bake cookies. Conversion: 1 pound = 1 lb = 454 grams. a.How many grams of sucrose did you purchase? 454 grams (g) = 1 pound (lb) 454 g * 5 = 2270 g A 5 pound bag of

*asked on September 23, 2015* -
## physics

an airplane is flying in a horizontal circle at a speed of 430 km/h if its wings are tilted 40 degrees to the horizontal what is the radius of the circle in which the plane is flying? assume that the required force is provided entirely by an "aerodynamic

*asked on May 27, 2009* -
## Org. Chem.

Is malonic acid polar or nonpolar? and does it hydrogen bond with water? with methyl alcohol? with hexane? I keep getting different results and would like some help please with explanation.

*asked on September 14, 2009* -
## Chemistry

Write the balanced equation for (aq) Pb(ClO3)2 and (aq) NaI. Include phases. What mass of precipitate will form if 1.50 L of concentrated Pb(ClO3)2 is mixed with .250 L of .110 M NaI? Assume the reaction goes to completion.

*asked on October 4, 2013* -
## Physics

A photon has a frequency of 7.3 × 10–17 Hz. Planck’s constant is 6.63 × 10–34 J•s. The energy of the photon, to the nearest tenths place, is × 10–50 J.

*asked on May 11, 2016* -
## Physics -Relativity

Question: If a muon is traveling at 70% of the speed of light, how long does it take to decay in the observer's rest frame (i.e., what is the observed lifetime of the muon)? Answer: =??? us

*asked on April 16, 2008* -
## Chemistry

If a solution containing 52.044 g of mercury(II) chlorate is allowed to react completely with a solution containing 15.488 g of sodium sulfate, how many grams of solid precipitate will be formed? How many grams of the reactant in excess will remain after

*asked on October 13, 2013* -
## Physics

You sit at the edge of a merry-go-round of radius 1.5 m. Your friends spin the ride faster and faster. When the period of rotation is 2.5 seconds, you slide off on a tangent. Determine the static coefficient of friction between you and the ride.

*asked on November 28, 2017* -
## Science

1. Which statement about subatomic particles is NOT true? (1 point) Protons and neutrons have almost the same mass. Protons and electrons have opposite charges. Unlike protons and electrons, neutrons have no charge. Protons and neutrons have the same

*asked on October 10, 2008* -
## geometry

The ratio of the angle measures of a pentagon is 4:5:3:8:7. What is the measure of the smallest angle?

*asked on February 10, 2010* -
## chemistry

Assuming equal concentration rank these by freezing points, Na3PO4, Li2Co3,NH4Cl, and Sn(NO3)4

*asked on January 27, 2013* -
## Chemistry

NaHCO3 (s) + HC2H3O2 (aq) ---> ?

*asked on October 4, 2013* -
## science

A boy and his skateboard have a combined mass of 64 kg. If he is moving with a speed of 3.2 m/s, and collides with a stationary skateboarder whose mass (including his skateboard) is 96 kg, with what speed will the two skateboarders move immediately after

*asked on February 9, 2013* -
## Chemistry

If a solution containing 52.044 g of mercury(II) chlorate is allowed to react completely with a solution containing 15.488 g of sodium sulfate, how many grams of solid precipitate will be formed? How many grams of the reactant in excess will remain after

*asked on October 13, 2013* -
## Physics

Light containing two different wavelengths passes through a diffraction grating with 1300 slits/cm. On a screen 16.0 cm from the grating, the third-order maximum of the shorter wavelength falls midway between the central maximum and the first side maximum

*asked on April 14, 2011* -
## Social Studies Crossword puzzle

I have a crossword puzzle for the Social Studies 7 B Unit 2 Lesson 8 These are the ones across 1. Wells tap into these underground water sources 2. A member of a religion that combines others teachings with Islam 3. The dry area on the opposite side of the

*asked on April 6, 2018* -
## Chemistry

102.0 MHz (typical frequency for FM radio broadcasting) Express your answer using four significant figures.

*asked on October 29, 2016* -
## Dr. Russ- Org. Chem.

Yes, there was a difference in my results between the solubilities of benzophenone in methyl alcohol and benzophenone in hexane. Benzophenone [essentially nonpolar (slightly polar due to the C=O bond)] was soluble in methyl alcohol, but only partially

*asked on September 15, 2009* -
## Chem.

If you had a mixture of benzene, toluene, and m-xylene, what would be the expected order of retention times? Explain. I know benzene would have a retention time of 3 mins, toluene about 4.8 mins, and m-xylene about 5.6 mins, right? Therefore, the expected

*asked on November 3, 2009* -
## chemistry

Outline a separation scheme for isolating pure isopentyl acetate from the reaction mixture. ( post lab question for the Banana oil lab)

*asked on July 9, 2013* -
## Org. Chem.

Why would hydrogen bonding not occur between benzophenone and water? or would it and why? Why does benzophenone and methyl alcohol H bond? And benzophenone and hexane don't? Why is there potential for H bonding between malonic acid and water and malonic

*asked on September 14, 2009* -
## physics

An explosion occurs at the end of a pier. The sound reaches the other end of the pier by traveling through three media: air, fresh water, and a slender metal handrail. The speeds of sound in air, water, and the handrail are 355, 1410, and 5380 m/s,

*asked on April 29, 2012* -
## Org. Chem.

Explain the results in terms of polarities and/or hydrogen bonding. - water and ethyl alcohol= miscible water is highly polar and ethyl alcohol has intermediate polarity. - water and diethyl ether= immiscible water is highly polar and diethyl ether is only

*asked on September 14, 2009* -
## chemistry

molecular and net ionic equations for FeCl3 + Na2S

*asked on June 21, 2011* -
## calc 2

(last one) ... Let f(t) be a function defined for all values of t. The Laplace Transform of f(t) is defined by: F(s)= ç[∘,‡](e^-st(f(t))dt). If the improper integral exists, Find the Laplace Transform for f(t)= sinhat

*asked on April 7, 2014* -
## Physics

Water moves through a constricted pipe in steady, ideal flow. At the lower point shown in the figure below, the pressure is 1.85x10^5 Pa and the pipe radius is 2.80 cm. At the higher point located at y = 2.50 m, the pressure is 1.28X10^5 Pa and the pipe

*asked on November 20, 2012* -
## algebra

Given the parent function of f(x) = x3, what is the value of h in the translated graph of f(x − h) + k?

*asked on December 13, 2016* -
## Calc

The monthly cost of driving a car depends on the number of miles driven. Lynn found that in May it cost her $380 to drive 480 mi. and in June it cost her $460 to drive 800 mi. a) Express the montly cost C as a function of the distance driven d, assuming

*asked on September 20, 2010* -
## Chemistry

An unknown organic compound is 40.00% C, 6.67% H and 53.33% O by mass. The formula weight of the unknown is 90.0g/mole. Find the empirical and molecular formulas for the unknown compound.

*asked on September 23, 2015* -
## Org. Chem.

1. Are the following soluble, insoluble, or partially soluble. - Benzophenone in hexane? - 1-octanol in hexane? I think soluble? - 1-butanol in water? in hexane? - methyl alcohol in hexane? I think partially soluble? Please help me and explaining would be

*asked on September 13, 2009* -
## Chemistry

The foul odor of rancid butter is due largely to butyric acid, a compound containing carbon, hydrogen, and oxygen. Combustion analysis of a 4.30-g sample of butyric acid produced 8.59g CO_2 and 3.52 g H_2O.Find the empirical formula for butyric acid.

*asked on September 17, 2010* -
## Heart of Darkness

1. Different settings. Consider how Kurtz and the pilgrims act differently in the following settings. • Belgium For this one I said they act very civilized because they want to keep up appearances, but I don't remember any specific examples • The Congo

*asked on December 6, 2015* -
## Calc

Find the functions a) f o g, b) g o f, c) f o f, d) g o g, and their domains. f(x)= square root of x, g(x)= cube root of 1-x These are my answers, but I am not sure about them and I only figured out one domain... that is the part that really confuses me.

*asked on September 20, 2010* -
## Chemistry

The flask here contains 10.0 mL of HCl and a few drops of phenolphthalein indicator. The buret contains .270 M NaOH. What volume of NaOH is needed to reach the end point of titration? What was the initial concentration of HCl?

*asked on October 4, 2013* -
## Calc.

Use a linear approximation (or differentials) to estimate the given number. Tan 44 degrees Please help.

*asked on November 15, 2010* -
## physics

A speeder driving down the road at a constant 20m/s passes a patrolman parked on the roadside. The patrolman waits 3 seconds then pursue the speeder accelerating at a constant 4m/s2. When does the patrolman catch the speeder

*asked on September 22, 2015* -
## chemistry

will the following solutions be acidic, neutral, or basic? Write the net ionic equation for any reaction that takes place. NH4Cl, KHCO3, LiClO4, NH4NO3, H2CO3, LiClO2, Ba(NO3)2

*asked on July 18, 2011* -
## Chemistry #27

Given that: H2 (g) + F2 (g) ---> 2HF (g) H(rxn)= -546.6 kJ 2H2 (g) + O2 (g) ---> 2H2O (l) H (rxn)= -571.6 kJ calculate the value for H(run) for... 2F2(g) + 2H2O (l) ---> 4HF (g) + O2 (g) _____kJ?

*asked on October 28, 2013* -
## Stiochiometry

Carbon dioxide is released into the air from the combustion of octane (C8H18). How much octane will you need to get 5.00 moles of carbon dioxide? What is the mass of the octane?

*asked on January 31, 2008* -
## PHYSICS

How much heat must be added to 1.0 kg of iron to raise its temperature from 20°C to 95°C? (ciron = 0.11 cal/g•°C)

*asked on July 3, 2013* -
## .....

what is the possessive noun in "the purses of the ladies"

*asked on February 14, 2011* -
## Math 9th grade slopes

A line connecting (5, 6) to another point has an undefined slope. What is the closest point on this line with whole number coordinates below (5, 6)?

*asked on May 27, 2011* -
## Statistics

Supposed (as is roughly correct) that each child born is equally likely to be a boy or a girl and that sexes of successive children are independent. If we let BG mean that the older child is a boy, and the younger child is a girl, then each of the

*asked on May 28, 2011* -
## Math (Area of Shapes)

Suppose that when pizza dough is rolled out it costs 25 cents per square foot, and that sauce and cheese when spread out on a pizza have a combined cost of 60 cents per square foot. Let's say sauce and cheese are always spread out to within 1 inch of the

*asked on October 28, 2012* -
## Chemistry #11

A solution of ethanol (C2H5OH) is prepared by dissolving 35.0 ml of ethanol in enough water to make 120.0 ml of solution. What is the molarity of the ethanol in this solution? 46.07 g= molar mass of ethanol .079 g/ml=density

*asked on October 14, 2013* -
## College Physics

A particle experiences a constant acceleration that is north at 100 m/s^2. At t=0, its velocity vector is 60 m/s east. At what time will the magnitude of the velocity be 100 m/s?

*asked on September 13, 2010* -
## Math

Three eights of the cast in a musical have to sing. What fraction of the cost does not have to sing?

*asked on February 5, 2015* -
## Chemistry 22

Table salt NaCl and sugar C12H22O11 are accidentally mixed. A 6.00 g sample is burned and 2.90 g of CO2 is produced. What was the mass percentage of the table salt mixture? Could you please show me all the way through if you can?

*asked on October 5, 2013* -
## physics

A 5-kg box is pushed across a horizontal floor by a 20-N force that is angled 30 degrees below the horizontal. What is the coefficient of kinetic friction between the box and the floor if the box is pushed at a constant speed?

*asked on July 10, 2013* -
## physics

a rock is dropped from a cliff falls one-third of it's total distance to the ground in the last second of it's fall. how high is the cliff?

*asked on August 26, 2010* -
## Science

How long does it take a sloth to digest its food? a.2 days b.2 months c.2 weeks d.2 hours

*asked on October 20, 2009* -
## chemistry

For the following chemical reaction, how many moles of silver iodide (AgI) will be produced from 4 mol of calcium iodide (CaI2)?

*asked on April 24, 2015* -
## Physics

I need to check my answers for the following: An Aston Martin V8 Vantage sports car has a maximum “lateral acceleration” of 0.96 “g’s”, after which the car begins to skid out of its turn. 2.1 Calculate the coefficient of static friction between

*asked on March 31, 2014* -
## Physics

A man lifts a 2.0 kg stone vertically with his hand at a constant upward velocity of 1.5 m/s. What is the magnitude of te total force of the stone on the man's hand?

*asked on September 13, 2010* -
## Algebra

To reduce 32 grams of a 25% solution of antiseptic to a 10% solution, how much distilled water should a pharmacist add?

*asked on March 2, 2010* -
## Chemistry

A student synthesized 6.895 g of barium iodate monohydrate by adding 30.00 mL of 5.912 x 10-1 M sodium iodate, NAIO3. 125 mL of distilled water as used to wash and transfer the precipitate, rather than 20 mL of chilled distilled water (at 4* C). The

*asked on October 7, 2011* -
## chemsitry

The molecular geometry of POCl3 is tetrahedral. What hybridization does this indicate for the central P atom? Why is the answer spy?

*asked on December 11, 2013* -
## URGENT math rate of change

What is the horizontal change between the points (-2, 5) and (4, 10)?

*asked on June 8, 2011* -
## maths

a light house flashes every 56 seconds. Another lighthouse flashes every 40 seconds. At 9 p.m. they both flash t the same time. What time will it e when they next both flash at the same time?

*asked on September 26, 2010* -
## Org. Chem.

are 1-octanol and 1-butanol polar or nonpolar? I think slightly polar?

*asked on September 14, 2009* -
## Physics

Anthony Rizzo hits a baseball in such a way that it leaves his bat traveling at 40.4 m/s at an angle of 26 degrees above the horizontal. When hit, the baseball is 1.2 m above the ground, is in fair territory, and is 127 meters away from a 3.5 m tall fence?

*asked on November 16, 2017* -
## CHEMISTRYYY

What mass of PCl3 forms in the reaction of 70.6 g P4 with 268 g Cl2 ? P4 + 6Cl2 → 4PCl3

*asked on February 6, 2015* -
## math

how many 2 card hands are possible with a 26 card deck?

*asked on March 6, 2012* -
## Physics

When a high-speed passenger train traveling at 124 km/h rounds a bend, the engineer is shocked to see that a locomotive has improperly entered onto the track from a siding and is a distance D=666 m ahead. The locomotive is moving at 21 km/. The engineer of

*asked on June 14, 2011* -
## Chemistry #30

A sample of Br2(g) takes 10.0 min to effuse through a membrane. How long would it take the same number of moles of Ar(g) to effuse through the same membrane?

*asked on October 13, 2013* -
## Organic chem.

I need to find examples of reagents used in performing chemical resolutions of acidic, basic, and neutral racemic compounds. I have searched all over the internet and cannot find anything... please help.

*asked on March 4, 2010* -
## chemistry

How many grams (of mass m) of glucose are in 355mL of a 5.50% (m/v) glucose solution?

*asked on November 4, 2013* -
## Chemistry

A certain gas has a density of 1.053 g/L at 25C and 752 mmHg. What is the molar mass of this gas?

*asked on October 15, 2013* -
## Chemistry #25

Calculate the average translational kinetic energy (sometimes just called average kinetic energy)...for one mole of gas at 381 K.

*asked on October 13, 2013* -
## Math

A farmer has 80 feet of fencing, which she plans to use to fence in a plot of land for a pigpen. If she chooses to enclose a plot along the broad side of her barn, what is the largest area that can be enclosed? (Note: The side along the barn will not

*asked on January 31, 2012* -
## 5th grade

How long does ti take a sloth to digest its food? a.2 days b.2 months c.2 weeks d.2 hours

*asked on October 20, 2009* -
## Math aglebra

I need help RIGHT NOW!!!!!!!!!!!!!! On the blueprints of Adam's office building, the length of his rectangular office space is 5 1/4 inches. If the actual length of Adam's office space is 10 1/2 feet, what is the scale of the blueprint?

*asked on November 23, 2016* -
## Calc

Recent studies indicate that the average surface temp. of the earth has been rising steadily. Some scientists have modeled the temp. by the linear function T= 0.02t + 8.50, where T is temp. in degrees Celsius and t represents years since 1900. What do the

*asked on September 20, 2010* -
## Chemistry

Copper is changed to copper(II) ions by nitric acid according to the following equation: 4HNO3 + Cu → Cu(NO3)2 + 2NO2 + 2H2O How many moles of HNO3 must react to produce 0.961 mol of NO2?

*asked on February 6, 2015* -
## coordinate algebra

The area of a rectangle is found by multiplying the length by the width: A = lw. A certain rectangle has an area of x2 + 7x + 12. Factor the trinomial to find the length and width of the rectangle. In the form of a paragraph, describe the process necessary

*asked on December 2, 2014* -
## Chemistry #26

where R=8.314 J/(mol·K) and ℳ is molar mass in kilograms per mole. Note that a joule is the same as a kg·m2/s2. What is the rms speed of N2 molecules at 335 K? What is the rms speed of He atoms at 335 K?

*asked on October 13, 2013* -
## world geography/geography

The forests of the Pacific Northwest are just one of the many different ______________ in the United States where many people work in the same industry. A. elevation regions

*asked on February 25, 2014* -
## Chemistry

Part 1: Find the % by mass of each element in camphor (C10H20O). Step 1: Find the atomic mass of each element in the molecule. Atomic Mass of C: 12.0107 Atomic Mass of H: 1.00794 Atomic Mass of O: 15.9994 Step 2: Find the mass combination of each element.

*asked on September 21, 2015* -
## Org. Chem.

If benzophenone is nonpolar, how come it is only partially soluble in hexane (nonpolar)? Also, can H bonding occur? Can H bonding occur between benzophenone and methyl alcohol? malonic acid and methyl alcohol? biphenyl and methyl alcohol? Please explain.

*asked on September 14, 2009* -
## Physics

A train moving with constant velocity travels 190 north in 14s and an undetermined distance to the west. The speed of the train is 36m/s. Find the direction of the train's motion relative to north. How far west has the train traveled?

*asked on February 7, 2013* -
## Physics PLEASE HELP ASAP :)

A small spherical insulator of mass 8.96 10-2 kg and charge +0.600 μC is hung by a thread of negligible mass. A charge of −0.900 μC is held 0.150 m away from the sphere and directly to the right of it, so the thread makes an angle θ with the vertical

*asked on January 28, 2013* -
## physics

A pelican ﬂying along a horizontal path drops a ﬁsh from a height of 5.5 m. The ﬁ!@#$%^&ravels 7.0 m horizontally before it hits the water below. What was the pelican’s initial speed? The acceleration of gravity is 9.81 m/s^2.

*asked on October 15, 2011* -
## trigonometry

Write the equation of the curve in its final position: the graph of y = tan (x) is shifted by (pi/6) units to the right, stretched by a factor of 3, then translated 8 units up.

*asked on March 27, 2011* -
## math

6. A lottery offers two options for the prize. Option A: $1000 a week for life Option B: $ 600 000 in one lump sum. The current expected rate of return for large investment is 7%/a, compounded weekly. a. Which option would the winner choose if s/he expects

*asked on January 17, 2011* -
## org. chem.

If benzophenone is nonpolar, how come it is only partially soluble in hexane (nonpolar)? Also, can H bonding occur? Can H bonding occur between benzophenone and methyl alcohol? malonic acid and methyl alcohol? biphenyl and methyl alcohol? Please explain.

*asked on September 14, 2009* -
## Calculus

a)The curve with equation: 2y^3 + y^2 - y^5 = x^4 - 2x^3 + x^2 has been linked to a bouncing wagon. Use a computer algebra system to graph this curve and discover why. b)At how many points does this curve have horizontal tangent lines? Find the

*asked on October 31, 2010* -
## Physics

A nuclear power plant has an electrical power output of 1200 MW and operates with an efficiency of 31%. If excess energy is carried away from the plant by a river with a flow rate of 1.0 multiplied by 10^6 kg/s, what is the rise in temperature of the

*asked on December 3, 2010* -
## Identifying patterns

If the pattern of polygons continues, how many sides will polygon 98 have? and there is a picture of polygon 1 which is a 3-sided triangle polygon 2- which is is a sqaure polygon 3- which is a 5 sided pentagon. polygon 4- which is a six sided hexagon

*asked on May 11, 2011* -
## Chemistry

How many moles of ammonium ions and how many moles of sulfate ions are contaiuned in a 0.400 mile sample of (NH4)2SO4? Referring to the 0.400 mole sample of (NH4)2SO4 on the previous page, how many atoms of N,H,O, and S, are contained in this sample?

*asked on September 23, 2015* -
## college statistics

the average length of time required for students to complete a test in a an introductory statistics course is found to be 50 minutes with a standard deviation of 12 minutes. if students are allowed 80 minutes to complete the test , approximately what

*asked on November 6, 2014*