Wednesday

November 25, 2015
Total # Posts: 88,286

**chemistry**

1 is D!
*November 17, 2015*

**chem**

for others facing these problems, 1.A 2.D 3.B 4.A 5.C
*November 17, 2015*

**Chemistry (Help)**

-35120 exothermic?
*November 17, 2015*

**Chemistry (Help)**

-75520 exothermic?
*November 17, 2015*

**Chemistry (Help)**

Calculate the DHrxn of C57H110O6 (s) + O2(g) --> CO2(g) + H2O(l) with DHf. C57H110O6(s) -390.70 O2(g) 0 CO2(g) -393.5 H2O(l) -285.840 I balanced the equation: 2C57H110O6 (s) + 163O2(g) --> 114CO2(g) + 110H2O(l) and my work: DHrxn = [224mol(-393.5+(-285.840))] - [165mol(-...
*November 17, 2015*

**Chemistry (Check)**

or -2551.916?
*November 17, 2015*

**Chemistry (Check)**

-2816 Exothermic?
*November 17, 2015*

**Chemistry (Check)**

Calculate the DHrxn of C6H12O6 (s) + O2 (g) --> CO2 (g) + H2O (l) with DHf. C6H12O6(s) -1260.04 O2(g) 0 CO2(g) -393.5 H2O(l) -285.840 I balanced the equation: C6H12O6 (s) + 6O2 (g) --> 6CO2 (g) + 6H2O (l) and my work: DHrxn = [12mol(-393.5+(-285.840))] - [7mol(-1260.04+0...
*November 17, 2015*

**chem**

can anyone help please
*November 17, 2015*

**chem**

can anyone help please
*November 17, 2015*

**chem**

anyone know how to work out these problems?
*November 17, 2015*

**chem**

anyone know how to work out these problems?
*November 17, 2015*

**chemistry**

no one knows these :(
*November 17, 2015*

**Algebra**

15 hours overtime
*November 17, 2015*

**chemistry**

How many milliliters of water has been dispensed if the initial buret reading was 0.45 mL and the final is 20.33 mL?
*November 17, 2015*

**Science**

Okay....Thank you for clarifying!
*November 17, 2015*

**Science**

How do the circulatory system and the endocrine system interact in helping to maintain homeostasis in humans? A. The endocrine system produces hormones that are transported by the circulatory system to target cells when changes are needed. B. The circulatory system provides a ...
*November 17, 2015*

**Health**

What are the answers?
*November 17, 2015*

**math**

A number cube is rolled 24 times and the results are recorded as follows: 2 ones, 10 twos, 6 threes, 3 fours, 1 five, and 2 sixes. What is the experimental probability of rolling an even number?
*November 17, 2015*

**college algebra**

To get the reciprocal of a function switch x & y values. F(x) = (3x-5)/(x-2) becomes (x-2)/(3x-5)
*November 16, 2015*

**Algebra**

5b-7
*November 16, 2015*

**Chemistry (Check)**

Calculate the DHrxn of C57H110O6 (s) + O2(g) --> CO2(g) + H2O(l) with DHf. C57H110O6(s) -390.70 O2(g) 0 CO2(g) -393.5 H2O(l) -285.840 I balanced the equation and my work: DHrxn = [224mol(-393.5+(-285.840))] - [165mol(-390.70+0)] = -87706.66 KJ/mol Is this right? If not, ...
*November 16, 2015*

**Chemistry (Check)**

668.2 KJ/mol? Endothermic
*November 16, 2015*

**Chemistry (Check)**

Calculate the DHrxn of C6H12O6 (s) + O2 (g) --> CO2 (g) + H2O (l) with DHf. C6H12O6(s) -1260.04 O2(g) 0 CO2(g) -393.5 H2O(l) -285.840 I balanced the equation and my work: DHrxn = [14mol(-393.5+(-285.840))] - [7mol(-1260.04+0)] = -690.48 KJ/mol Is this right? If not, what ...
*November 16, 2015*

**Chemistry (Check)**

The bond strengths of the compounds HF, HCl, HBr, and HI are as follows: compound bond strength, kJ/mol HF 569.87 HCl 431.62 HBr 366.35 HI 298.407 Briefly explain why the bond strengths are ranked in this order. My guess is: They are ranked in this order because of the ...
*November 16, 2015*

**physics**

A 4 . 7 kg mass weighs 39 . 95 N on the surface of a planet similar to Earth. The radius of this planet is roughly 6 . 2 × 10 6 m. Calculate the mass of of this planet. The value of the universal gravitational constant is 6 . 67259 × 10 − 11 N · m 2 / ...
*November 16, 2015*

**Biology**

Chemical Formula: 6CO2 + 12H2O + light --> C6H12O6 + 6H2O + 6O2
*November 16, 2015*

**Biology**

What is the overall chemical formula for photosynthsis? 6Co2+6H2O--->C6H12O6+6O2 Where does the energy come from in photosynthesis? From Sunlight? What is the relationship between photosynthesis and respiration Photosynthesis makes the glucose that is used in cellular ...
*November 16, 2015*

**Spanish **

Conjugate the verbs in the two sentences: 1. Mis padres me compraron un coche que __________ (ir; yo) a usar para la universidad. 2. Llamé a todas las personas que ___________ (poder) para notificarles del cambio.
*November 16, 2015*

**Spanish **

Would these phrases use the indicative or subjunctive? Explain why? Thank you!! 1) Puedes hacer lo que ______________ (querer). 2) El equipo que ____________ (ganar) el Superbowl tendrá después una entrevista con el presidente de los EEUU. 3) Ellos harán ...
*November 16, 2015*

**algebra**

the sum of 12 and twice my age
*November 16, 2015*

**Math**

Estimate using a rate per 100 19% of 288 =
*November 16, 2015*

**Math**

9.5 !! Thanks Miss Sue
*November 16, 2015*

**Math**

A group of friends went on a hiking trip. They planned to hike a total of 38 miles. They want to complete 25% of the hike by the end of the first day. About how many miles should they hike the first day?
*November 16, 2015*

**Math**

the perimeter of a rectangular garder is 100 feet the length of the garden is 8 feet longer than twice the width I need 2 linear equations
*November 16, 2015*

**Quick English check- ms sue**

Select the term that is best evoked by each of the scenarios below. Use complement, contend efficacious, emulate, engross, exploit, facile, implicit, industrious, replicate. 1. The representatives appeal for aid for the disaster victims was so effective that aid literally ...
*November 16, 2015*

**Geography**

Who were the boat people
*November 16, 2015*

**PHYSICS**

The density of ice is 917 kg/m3, and the density of sea water is 1025 kg/m3. A swimming polar bear climbs onto a piece of floating ice that has a volume of 5.70 m3. What is the weight of the heaviest bear that the ice can support without sinking completely beneath the water?
*November 16, 2015*

**PHYSICS**

A dentist's chair with a patient in it weighs 2180 N. The output plunger of a hydraulic system begins to lift the chair, when the dentist's foot applies a force of 73.6 N to the input piston. Neglect any height difference between the plunger and the piston. What is the...
*November 16, 2015*

**Geography**

Shared by many people?
*November 16, 2015*

**Geography**

Yes about Paris. First question : Enhance their security Second question : Peace will not prevail unless people take action to stop these tragedies from happening such as better security? Third question : Try and locate the movement of ISIS?
*November 16, 2015*

**Geography**

What should Europeans and the USA do to prevent tragedies such as this? Will healing and peace prevail or more bloodshed?What should the world do now to combat ISIS?
*November 16, 2015*

**Physics**

i don't understand how u did this??
*November 16, 2015*

**Physics**

three cars accelerate while moving in the positive direction rank the cars in order of increasing acceleration from most negative to most positive. *car 1 speeds up from 25 m/s to 35 m/s in 10 sec * car 2 speeds up from 0 to 30 m/s in 15 sec *car 3 slows down from 32 m/s to 12...
*November 16, 2015*

**Physics**

the winner of the drag race was traveling with a speed of 140.3 m/s (313.9 mph) at the end of the quarter mile course the car started from rest and had an average acceleration of 30.4 m/s^2. what was the winning time for this race v=140.3 m/s a=30.4 m/s^2 t=? 140.4/30.4= 4.6 m/s
*November 16, 2015*

**Physics**

so the answer is v= 3.96?
*November 16, 2015*

**Physics **

A chameleon extends its tongue to capture a tasty insect. The tongue accelerates at 33 m/s2 for 0.12 seconds to make the capture. what is the speed of the chameleons tongue when it grabs the insect?
*November 16, 2015*

**Geometry**

If line segment WP is an angle bisector, m<HWA=(7s+16), m<PWA=15 find s, and m<HWA.
*November 16, 2015*

**Science**

btw, all my answers were right
*November 16, 2015*

**Science**

Which of the following gases was most likely present in Earth's earliest atmosphere? A. nitrogen B. hydrogen* C. argon D. oxygen Which of the following statements accurately describes the development of the geologic time scale? A. Scientists developed the geologic time ...
*November 16, 2015*

**Algebra**

I got it already but thanks anyways Steve :)
*November 16, 2015*

**Algebra**

In a table, how do you tell if y varies directly with x and write an equation if it does?
*November 16, 2015*

**SS**

What is an example of a person in history who broke soceital rules?
*November 16, 2015*

**SS**

What is an example of a criminal or bad person in Babylon?
*November 16, 2015*

**Science CHECK ANSWERS PLZ**

Which of the following gases was most likely present in Earth's earliest atmosphere? A. nitrogen B. hydrogen* C. argon D. oxygen Which of the following statements accurately describes the development of the geologic time scale? A. Scientists developed the geologic time ...
*November 16, 2015*

**math**

3*13 - 2 - 10 + 12/2
*November 16, 2015*

**Algebra**

assuming the same tax bracket, etc. (3030/5200)*(57/52)
*November 16, 2015*

**Physics**

a boy runs 10m/sec at 10m/sec and he walks for 30 sec at 10m/sec what is the average of speed of the boy ? A\ 5M/S B/ 20M/S C/15M/S D/10M/S E/ None
*November 16, 2015*

**10th grade**

Ravi resigned----------illness
*November 16, 2015*

**math**

Could someone please check my answer to this question: Evaluate the expression [(x^n)(y) + (y^n)] ^-2n for x=-2, y=3 and n=-1 =[(x^-1)(y)+(y^-1)]^-2(-1) =[(x^-1)(y)+(y^-1)]^2 =[(x^-2)(y^2)+(y^-2) =y^2/x^2(y^2) =3^2/(-2)^2(3^2) =9/4(9) =9/36 =1/4
*November 15, 2015*

**Algebra 1**

Evaluate: 1 5 9 × 1 8 Give your answer in its simplest form.
*November 15, 2015*

**Physics HELP**

How would I solve this problem? A plane travels 4300 m at an angle of 49 degrees to the ground, then changes direction and travels 6500 m at an angle of 21 degrees to the ground. What is the magnitude and direction of the planes tot displacement?
*November 15, 2015*

**SOC 320**

Which of the following is among the Courts’ means of influencing implementation? (Points : 1) Judicial review of administrative rules and rule making Direct oversight of executive branch agencies Routine judicial review of appropriations Intervening in policy cases they ...
*November 15, 2015*

**Chemistry**

I'm confused. Why do you use log and why do you do 1/H2SO4? I found this equation in our textbook: Ecell=Eocell-(RT/nFl)nQ When I use that equation I get 2.00, when I use the equation you've given I get 2.05. I know it's a small difference but why? Thank you
*November 15, 2015*

**Chemistry **

Given: PbSO4 + 2e− Pb + SO42− E° = -0.356 V PbO2 + 4H+ + SO42− + 2e− PbSO4 + 2H2O E° = 1.685 V Determine the cell voltage of the lead storage battery when the concentration of sulfuric acid is 4.00 M. Where do I start, thank you
*November 15, 2015*

**physics**

When a wood shelf of mass 7.2 kg is fastened inside a slot in a vertical support as shown in (Figure 1) , the support exerts a torque on the shelf. Assume that the slot exerts two vertical forces on the shelf, at points A and B. Detrmine the force exerted on the shelf by the ...
*November 15, 2015*

**physics**

When a wood shelf of mass 7.2 kg is fastened inside a slot in a vertical support as shown in (Figure 1) , the support exerts a torque on the shelf. Assume that the slot exerts two vertical forces on the shelf, at points A and B.
*November 15, 2015*

**Maths **

Statistics The marks scored by a sample of 56 students are summarised by: N=56 Sum of x =3026 sum of(x-the mean)^2 =15378 A) calculate the mean and the standard deviation Mean I got - 54.04 (2.dp) Standard deviation I got - 16.72 (2.dp) Is this correct? B) the formula y=1.2x-...
*November 15, 2015*

**Physics HELP**

A bug on a picnic table travels 10 cm east, then 18 cm northward, and finally 20 cm westward. What is the bugs displacement relative to its original position?
*November 15, 2015*

**PLEASE I NEED HELP MS SUE**

in the heart blood flows from the right atrium to the right ventricle where it is pumped to the ______ openstudy
*November 15, 2015*

**math**

An aeroplane flies due north from Ikeja Airport for 500km. It then flies on a bearing of 060 degrees for a further distance of 300km before overflying a road junction.Calculate a. The distance of the aeroplne from Ikeja Airport when it was directly above the road junction. B....
*November 15, 2015*

**Math**

What is the numerical expression for 8[(20-4)-6]
*November 15, 2015*

**maths plz help**

Painters A and B take 3 hours to paint a room Painters B and C take 5 hours to paint the same room Painters A and C take 7 hours to paint the same room How long would it take all three to paint the same room?
*November 15, 2015*

**Physics**

If the magnetic field in a traveling EM wave has a peak value of 17.9nT, what is the peak value of the electric field strength?
*November 15, 2015*

**math**

is (3,7) correct
*November 15, 2015*

**math**

solve the system by substitution -4x-5y=-47 x=2y-11
*November 15, 2015*

**Maths**

Statistics The marks scored by a sample of 56 students are summarised by: N=56 Sum of x =3026 sum of(x-the mean)^2 =15378 A) calculate the mean and the standard deviation Mean I got - 54.04 (2.dp) Standard deviation I got - 16.72 (2.dp) Is this correct? B) the formula y=1.2x-...
*November 15, 2015*

**physics**

A disk shaped yoyo (m=220 grams) has a 70 cm long string. The radius of the central winding peg is 2.5 mm, the outer radius of the yoyo is 5.6 cm. A) How much Torque is applied to this yoyo by the string? B) How long until the yoyo hits the bottom of the throw? C) What is the ...
*November 15, 2015*

**Chemistry **

10000 tonnes of iron reacted in a blast furnace Fe2O3 calculate the typical mass of iron produced each day
*November 15, 2015*

**PHYSICS**

A BALL IS PROJECTED VERTICALLY UPWARD FROM THE TOP OF A TOWER 60MITRE HIGH WITH A VELOCITY OF 30MITRE PER SECONDS.WHAT IS THE MAXIMUM HEIGHT ABOVE THE GROUND LEVEL?HOW LONG DOES IT TAKE TO REACH THE GROUND?
*November 15, 2015*

**Physics**

rotating space station has radius 1380 m, measured from the center of rotation to the outer deck where the crew lives. What should the period of rotation be if the crew is to feel that they weigh one-half their Earth weight?
*November 15, 2015*

**Biology**

simulate a 24 hour day 12 hours of light 12 hours of dark how many snails and plants do you ened to keep a stable environment
*November 14, 2015*

**Biology**

Animals breathe in ___ and breathe out __ In sunlight plants take in ___ and realease __
*November 14, 2015*

**Biology**

What gas do plants give off in the light
*November 14, 2015*

**Biology**

Why don't we run out of the important gases that we need to stay alive?
*November 14, 2015*

**chemistry**

Consider an atom traveling at 1% of the speed of light. The de Broglie wavelength is found to be 9.50 × 10–3 pm. Which element is this?
*November 14, 2015*

**Centripetal acceleration**

Is this right? Tarzan plans to cross a gorge by swinging in an arc from a hanging vine. If his arms are capable of exerting 1350 N on the vine, what is his acceleration at the point where the vine makes an angle of 45 degrees from the vertical assuming maximum speed at this ...
*November 14, 2015*

**Government**

To what extent do cabinet heads control the bureaucracy?
*November 14, 2015*

**Physics**

Tarzan plans to cross a gorge by swinging in an arc from a hanging vine. If his arms are capable of exerting 1350 N on the vine, what is his acceleration at the point where the vine makes an angle of 45 degrees from the vertical assuming maximum speed at this point. His mass ...
*November 14, 2015*

**algebra**

eq 1: y miles/(6 mph + x mph)=3 hr eq 2: y miles/(6 mph - x mph)=5 r multiply both sides by the numerator on the left eq 1: y =18 + 3x eq 2: y =30 - 5x subtract equation 2 from equation 1 0=-12 + 8x 12=8x 12/8+x
*November 14, 2015*

**algebra**

Chen's motorgoat took 3 hr to make a treip downstream with a 6-mph current. The return trip against the same current took 5 hr. Find the speed of the boat in still water.
*November 14, 2015*

**PE**

How does breathing change during exercise? Rate and depth decrease Rate and depth increase Rate increases and depth decreases Rate decreases and depth increases I think Rate increases and depth decreases is correct, can someone confirm or object? Danke.
*November 14, 2015*

**Chemistry **

Given the following half-reactions and their standard reduction potentials, Ni2+ + 2e− Ni E° = -0.25 V 2H+ + 2e− H2 E° = 0.00 V Ag+ + e− Ag E° = 0.80 V a spontaneous reaction will occur between: a. Ni2+ and H2 b. H+ and Ag c. Ag+ and Ni d. Ni2+ ...
*November 14, 2015*

**Riddle**

Reflection
*November 14, 2015*

**Riddle **

to all things and men I appertain and yet by some am shunned and distend. Fonder me and ogle me till your Insane ,but no blow can harm me cause me pain. Children delight in me ,elders take fright, fair maids rejoice and spin. Cry and I weep,yawn and I sleep,smile and I shall ...
*November 14, 2015*

**Spanish **

Would you use indicative or subjective in this sentence? Explain why? María prefiere que no _________________ (haber) mucha gente en la playa. (I think that you would use subjective because "haber" can count as a subjective change and it has a verb of influence)
*November 14, 2015*

**Health**

u stupid
*November 14, 2015*

**physics**

The AM frequencies of a radio dial range from 550 kHz, and the FM frequencies range of 88.0 MHz to MHz. all of these radio waves travel at a speed of 3.0x10^8 m/s, what are the wavelenght ranges of a.) the aM brand b.) FM brand
*November 14, 2015*

**physics**

A circular disk of 10cm radius is charged uniformly with a total charge of Q. Find the electric field intensity at a point 20cm away from the disk along its axis
*November 14, 2015*