answer

watching

views

26 Nov 2017

62. Calculate Ecell for each balanced redox reaction and determine if the reaction is spontaneous as written. a. O2(g) + 2 H2O(1) + 4 Ag(s) — 4OH(aq) + 4 Agt(aq) b. Br (1) + 2 (aq) — 2 Br (aq) + 12(s) c. PbO2(s) + 4H+(aq) + Sn(s) — Pb2+ (aq) + 2 H2O(l) + Sn²+ (aq)

word_media_image1.png

answer

watching

334

views

For unlimited access to Homework Help, a Homework+ subscription is required.

You have 0 free answers left.
Get unlimited access to 3.8 million step-by-step answers.

Get unlimited access

Already have an account? Log in

Keith LeannonLv2

28 Nov 2017

Unlock all answers

Get 1 free homework help answer.

Already have an account? Log in

Related questions

Fill in the nine gaps in this table.
Symbol B
Protons 19
Neutrons 20
Electrons 18
Mass number 11 40

Identify the unknown particle (X) in the following equations fornuclear decay, and state whether each process is alpha decay, betadecay, or gamma decay. (Type your answer according to this format:4 2 He represents . Use gamma to enter ?.)
(a) ? X + -
X =

(b) ? + X
X =

(c) ? + X
X =

Actinium-225 () undergoes alpha decay.
(a) Write the equation. (Enter the mass number in the first raisedbox, the atomic number in the second lower box, and the element,with charge if necessary, in the third box.)
? + He

(b) The daughter formed in part (a) undergoes beta decay. Write theequation. (Enter the mass number in the first raised box, theatomic number in the second lower box, and the element, with chargeif necessary, in the third box.)
? + e

Classify each of the following materials as an element, compound,heterogeneous mixture, or homogeneous mixture.
(a) concrete
element
compound
heterogeneous mixture
homogeneous mixture

(b) clear apple juice
element
compound
heterogeneous mixture
homogeneous mixture

(c) nitrogen
element
compound
heterogeneous mixture
homogeneous mixture

(d) ozone
element
compound
heterogeneous mixture
homogeneous mixture

Refer to the figure below. Find the approximate solubility (g/100 gwater) of sugar at 20Â°C.
g/100 g of water

Give the symbol for each of the following elements.
(a) lead

(b) sodium

(c) oxygen

Give the name of each element.
(a) Cu

(b) Bi

(c) Ti

Volcanoes emit much hydrogen sulfide gas, H2S, which reacts withthe oxygen in the air to form water and sulfur dioxide, SO2. Every53 tons of H2S reacts with 75 tons of oxygen and forms 28 tons ofwater. How many tons of SO2 are formed?

An antacid tablet weighing 0.939 g contained calcium carbonate asthe active ingredient, in addition to an inert binder. When an acidsolution weighing 56.233 g was added to the tablet, carbon dioxidegas was released, producing a fizz. The resulting solution weighed56.954 g. How many grams of carbon dioxide were produced?

Calculate (to the nearest 0.1 u) the formula mass of thesecompounds.
(a) sodium phosphate, Na3PO4
u

(b) methane, CH4
u

(c) silver cyanide, AgCN
u

Calculate (to the nearest 0.1 u) the formula mass of thesecompounds.
(a) silver carbonate, Ag2CO3
u

(b) calcium bromide, CaBr2
u

(c) magnesium hydroxide, MgOH
u

Balance these chemical equations. (Use the lowest possiblecoefficients.)
(a) O2 + N2H4 ? H2O2 + N2

(b) Sr + H2O ? Sr(OH)2 + H2

(c) NH3 + O2 ? N2 + H2O

(d) Al + Fe3O4 ? Al2O3 + Fe

(e) Fe(OH)2 + O2 + H2O ? Fe(OH)3

(f) Pb(NO3)2 ? PbO + NO2 + O2

(a) Calcium and chlorine react to give calcium chloride in acombination reaction. Write and balance the equation. (Type youranswer using the format CO2 for CO2. Use the lowest possiblecoefficients.)

Ca + ?

(b) Heating decomposes Na2CO3 to sodium oxide and carbon dioxide.Write and balance the equation. Type your answer using the formatCO2 for CO2. Use the lowest possible coefficients.)

Na2CO3 ? + CO2

Write and balance the reaction for the complete combustion ofmethanol, CH3OH. (Type your answer using the format CO2 for CO2.Use the lowest possible coefficients.)

x.Hm

I just need help in the three questionI figure the last question

1)Consider an oxygen molecule (O2) rotating inthe xy plane about the z axis. The axis

passes through the center of the molecule,perpendicular to its length. The mass of each

oxygen atom is 2.66 x 10

-26 kg, and at room temperature the average separation between

the two atoms is

d=1.21 x 10-10 m (the atoms are treated as point masses).a) Calculate

the moment of inertia of the molecule about the zaxis. b) If the angular speed of the

molecule about the

z axis 4.60 x 1012 rad/s, what is its rotational kineticenergy?

Answer: a) 1.95 x 10

-46 kg.m2 b) 2.06 x 10-21 J

2) A wheel rotates with a constant angularacceleration of 3.50 rad/s2. If the angular speed

of the wheel is 2.00 rad/s at

ti = 0, a) through what angle does the wheel rotate in2.00 s?

Answer a) 6300

3)A uniform rod of length L and mass M is free to rotate on africtionless pin passing

through one end as shown in question 4 below. Therod is released from rest in the

horizontal position. a) What is its angular speedwhen it reaches its lowest position?

b) Determine the linear speed of the center ofmass and the linear speed of the lowest

point on the rod when it is in the verticalposition.

Answer: a)

3g b) Center of mass speed =3gL

1 ;

Linear speed of the lowest point =3gL

(Hint, use mechanical energy conservation)

4 A uniform rod of length L and mass M is attached at one endto a frictionless pivot and is

free to rotate about the pivot in the verticalplane, as shown in Figure below. The rod is

released from rest in the horizontal position. a)What is the initial angular acceleration of

the rod and b) the initial linear acceleration ofits right end? Answer: a)

Answer: a)

g b) Center of mass speed = 3gL

1 ;

Linear speed of the lowest point =3

(Hint, use mechanical energyconservation)

A boy in a wheelchair (total mass 50.5 kg) has a speed of 1.40 m/s at the crest of a slope 2.40 m high and 12.4 m long. At the bottom of the slope, his speed is 6.50 m/s. Assume air resistance and rolling resistance can be modeled as a constant friction force of 41.0 N. Find the work he did in pushing forward on his wheels during the downhill ride.

2 Answers

Relevance

electron1
Lv 7

4 years ago

There are two forces that cause the wheelchair to accelerate. These two forces are the component of the wheelchair’s weight that is parallel to the hill and the force the boy exerts. The net force on the wheelchair is equal to the sum of these two forces minus the friction force. Let’s use the following equation to determine the acceleration.

vf2 = vi^2 + 2 * a * d

6.5^2 = 1.4^2 + 2 * a * 12.4

24.8 * a = 40.29

a = 40.29 ÷ 24.8

This is approximately 1.62 m/s^2.

Net force = 50.5 * 40.29 ÷ 24.8 = 2034.645 ÷ 24.8

This is approximately 82 N.

Force parallel = 50.5 * 9.8 * 2.40 ÷ 12.4 = 1187.76 ÷ 12.4

This is approximately 95.8 N. This force and the force that the boy exerts are the forces that cause the wheelchair to accelerate.

Net force = F + (1187.76 ÷ 12.4) – 41

Set the two net forces equal to each other.

F + (1187.76 ÷ 12.4) – 41 = 2034.645 ÷ 24.8

F = 41 + (2034.645 ÷ 24.8) – (1187.76 ÷ 12.4)

F is approximately 27.3 N

Work = [41 + (2034.645 ÷ 24.8) – (1187.76 ÷ 12.4)] * 12.4 = 337.9625 J
JupiterSky
Lv 6

4 years ago

His change in kinetic energy is due to gravitational- and his own work,

while the friction does negative work.

∆K = ∆U +∆W + ∆Wf

½m(Vf²−Vi²) = mgh + ∆W + Ff*d

∆W = ½m(Vf²−Vi²) − mgh − Ff*d

∆W = ½*50.5(6.5²−1.4²) − (50.5*9.8*2.4) − (−41*12.4)

∆W = 508 J

Still have questions? Get your answers by asking now.

Next Question

---

asked in Science & MathematicsPhysics · 8 years ago

What is the spring constant? please help me!!!!?

A block of mass 487 g is pushed against the
spring (located on the left-hand side of the
track) and compresses the spring a distance
4.7 cm from its equilibrium position (as shown
in the ﬁgure below). The block starts from
rest, is accelerated by the compressed spring,
and slides across a frictionless horizontal track
(as shown in the ﬁgure below). It leaves the
track horizontally, ﬂies through the air, and
subsequently strikes the ground.
acceleration = 9.81
 
A) What is the spring constant?
B)What is the speed v of the block when it leaves
the track?
C) What is the total speed of the block when it
hits the ground?
...Show more

Update:

Height Above ground = 1.9 m
Lands = 4.59m away

What is the spring constant? please help me!!!!?

3 Answers

Relevance

Jánošík
Lv 7

8 years ago

Favorite Answer

I'm sure there is some crucial information in "the figure below" !!!

Edit:

OK... now we got something to work with ... ;-)

Time needed to fall a vertical distance of 1.9 m is:

t = √( 2h / g )

t = √[ 2×(1.9 m) / (9.81 m/s²) ]

t = 0.6224 s

In that time, the block must travel a horizontal distance of 4.59 m, so the horizontal velocity is:

r = v×t

(4.59 m) = v×(0.6224 s)

v = 7.37 m/s < - - - - - - - - - - - - - - - - - answer B

That is also the speed of the block as it leaves the spring.

Its kinetic energy at that time is:

KE = m×v²/2

KE = (0.487 kg)×(7.3749 m/s)²/2

KE = 13.244 J

That is also the elastic potential energy stored in the spring at maximum compression. So the spring constant is:

KE = PEe = k×d²/2

(13.244 J) = k×(0.047 m)²/2

k = 12 N/m < - - - - - - - - - - - - - - - - - - answer A

The gravitational potential energy of the block on the table is:

PEg = m×g×h

PEg = (0.487 kg)×(9.81 m/s²)×(1.9)

PEg = 9.077 J

The total energy of the block on the table is:

TE = PEg + PEe

TE = (9.077 J) + (13.244 J)

TE = 22.32 J

When hitting the ground, all that energy is converted to kinetic energy, so

TE = KE = m×v²/2

(22.32 J) = (0.487 kg)×v²/2

v = 9.57 m/s < - - - - - - - - - - - - - - - - - - answer C

...Show more
Technobuff
Lv 7

8 years ago

There must be a height above ground and a distance from the end of the track on the "as shown in the figure below".??
STALKER
Lv 4

8 years ago

use f=kl

where k is the spring constant and l is extension from the natural length.

k=f/l

since you have mass in grams. use w=mg

w=0.487 x 9.8 = 4.77N

Now use the equation,

k=4.77/4.7

k=1.012

Note: my answer could be wrong since I do not know the springs original length from the diagram shown. But, the method of working out spring constant is same.

...Show more

Still have questions? Get your answers by asking now.

Next Question

ひいらぎ

Lv 5

asked in Science & MathematicsPhysics · 1 decade ago

Physics Momentum, Rolling?

Pat builds a track for his model car out of wood. The track is 10.00 cm wide and 3.00 m long, and is solid. The runway is cut such that it forms a parabola by the equation y=(x - 3)^2/9. Locate the horizontal position of the center of gravity of this track.
 
A washing machine load in the "spin" cycle, (much like a centrifuge used to separate fluids), can be modeled as a cylinder which has zero density toward the center, and starting from some inner radius where the clothes (or fluids) begin, increases in density as you move radially outward. The washing machine has density of clothes (in SI units) of p=14r+5, a height of 0.51 m, and only has clothes present from inner radius 0.2m out to 0.7m from the center.
-What is the moment of Inertia of the wash load?
-What is the power of motor that drives the clothes from rest up to 4 rev/sec, in 14 seconds if the basin has moment of Inertia of 4 kg*.m2
...Show more

Physics Momentum, Rolling?

1 Answer

Relevance

Anonymous

1 decade ago

Favorite Answer

I can't visualize the first problem.

The second: Moment of inertia is I = m r^2. In a shell of thickness dr there is a mass of p * 2 * pi * r * h * dr. The moment of inertia of the shell is 2 pi h p r^3 dr. Now integrate this from r = 0.2m to r = 0.7m.

Kinetic energy is 1/2 m v^2. In rotations the moment of inertia is like the mass and the angular velocity is like the velocity, so rotational energy is 1/2 I omega^2. Omega is in rad/s. The total inertia of the system is the sum of the inertia of the clothes and the basin. Divide the energy by the time needed to get the power.

...Show more

Still have questions? Get your answers by asking now.

Next Question

asked in Science & MathematicsPhysics · 1 decade ago

Physics:You and your friends push a 75-kg...Help!?

You and your friends push a 75-kg greased pig up an aluminum slide at the county fair, starting from the low end of the slide. The coefficient of kinetic friction between the pig and the slide is 0.070.
 
(a) All of you pushing together (parallel to the incline) manage to accelerate the pig from rest at the constant rate of 4.9 m/s2 over a distance of 1.8 m, at which point you release the pig. The pig continues up the slide, reaching a maximum vertical height above its release point of 50 cm. What is the angle of inclination of the slide? __degree
 
(b) At the maximum height the pig turns around and begins to slip down the slide, how fast is it moving when it arrives at the low end of the slide? __m/s
...Show more

Physics:You and your friends push a 75-kg...Help!?

1 Answer

Relevance

Anonymous

1 decade ago

Favorite Answer

♣the distance the pig was pushed up is

s=0.5*a*t^2, where s=1.8m, a=4.9m/s^2, t is time of push-up;

speed of the pig gained after s=1.8m is v=a*t; thus v^2=2as;

♠ kinetic energy of the pig at the moment it’s released after push-up is

E=0.5*m*v^2, which is enough for the pig to move by itself L distance more along the ramp, where L=h/sin(b), h=50cm=0.5m, b is angle in question;

♦pig’s potential energy at vertex (when stopped) is E1=mgh;

the energy E2=E-E1 is gone on friction, that is E2=f*L is work of friction, where

f=μ*w1, w1=mg*cos(b) is component of pig’s weight normal to the aluminum ramp; or;

f= μ*mg*cos(b);

♦Thus E2=E-E1; or; f*L = 0.5*m*v^2 –mgh; or;

(μ*mg*cos(b)) * (h/sin(b)) =0.5*m* 2as –mgh; or;

μ*gh*cos(b)/sin(b) =as –gh, hence cot(b) =(as –gh)/(μ*gh), hence

(a); b=atan(μ*gh/(as-gh))= atan(0.07*9.8*0.5/(4.9*1.8 -9.8*0.5)) =5°;

♥ pig’s potential energy above the low end of the ramp is

W= mg*(s*sin(b) +h); pig’s ramp position is p=s +L = s + h/sin(b);

Pig’s final kinetic energy is W1=W-W2, where W2=f*p is work of friction;

and W1=0.5*m*v^2; thus

0.5*m*v^2 = mg*(s*sin(b) +h) – μ*mg*cos(b)*(s + h/sin(b));

v^2 =2g*(s*sin(b) +h)*(1 –μ*cot(b)) =2.575;

(b); v =1.605 m/s;

...Show more

Still have questions? Get your answers by asking now.

+100

Join Yahoo Answers and get 100 points today.

Weekly leaderboard

Home

Homework Help 3,900,000

Physics 110,000

62. Calculate Ecell for each balanced redox reaction and determine if the reaction is spontaneous as written. a. O2(g) + 2 H2O(1) + 4 Ag(s) — 4OH(aq) + 4 Agt(aq) b. Br (1) + 2 (aq) — 2 Br (aq) + 12(s) c. PbO2(s) + 4H+(aq) + Sn(s) — Pb2+ (aq) + 2 H2O(l) + Sn²+ (aq)

Unlock all answers

Related textbook solutions

Physics: Principles with Applications

Related questions

2 Answers

What is the spring constant? please help me!!!!?

3 Answers

Physics Momentum, Rolling?

1 Answer

Physics:You and your friends push a 75-kg...Help!?

1 Answer

Trending Questions

Related Documents

KP222 Lecture Notes - Lecture 3: Atp Synthase, Activation Energy, Cori Cycle

KP222 Chapter Notes - Chapter 3: Thermodynamics, Lactate Dehydrogenase, Bond Energy

PHYSIC 211 Lecture Notes - Lecture 19: Calcium Hydride, Calcium Sulfate, Sulfite

Weekly leaderboard