# Questions Asked onFebruary 24, 2012

1. ## chemistry

is the low solubility of KHT a result of an unfavorable delta H or an unfavorable delta S value

2. ## physics

two charged bodies exert a force of 86N on each other. If they are moved so that they are 6 times farther apart, what is the new force that they will exert on each other?

3. ## chemistry

In a particular redox reaction, Cr is oxidized to CrO42– and Cu2 is reduced to Cu . Complete and balance the equation for this reaction in acidic solution. Phases are optional. Cr + Cu2+ = CrO42- + Cu+

4. ## statistics

A student scored 84 points on a test where the mean score was 79 and the standard deviation was 4. Find the student's z score, rounded to 2 decimal places

5. ## physics

. An inquisitive physics student and mountain climber climbs a 50.0-m cliff that overhangs a calm pool of water. He throws two stones vertically downward, 1.00 s apart, and observes that they cause a single splash. The first stone has an initial speed of

6. ## more math needed

You have a 70% dextrose solution. How many grams of dextrose are in 400ml?

7. ## chemistry

Separate this redox reaction into its component half-reactions. O2 + 2Zn -->2ZnO

8. ## Chemistry 101

if 95j of heat is added to a pure gold coin with a mass of 16 grams, what is its temperature change? Specific heat capacity of gold is 0.128 j/g degrees C.

9. ## chemistry

The quantity of antimony in a sample can be determined by an oxidation-reduction titration with an oxidizing agent. A 6.35-g sample of stibnite, an ore of antimony, is dissolved in hot, concentrated HCl(aq) and passed over a reducing agent so that all the

10. ## Calculus

The fuel efficiency, E, in litres per 100 km, for a car driven at speed v, in km/h is E(v)=1600v/(v^2+6400) a) determine the legal speed that will maximize the fuel efficiency using speed limit of 50 km/h

11. ## chemistry

Separate this redox reaction into its component half-reactions. Cl2 + 2Na --> 2NaCl

12. ## chemistry

a quantity of gas is collected over water at 15C. The manometer indicated a pressure of 24.0kPa. what would be the pressure of the dry gas?

13. ## physics

A skater of mass 74.0 kg initially moves in a straight line at a speed of 4.60 m/s. The skater approaches a child of mass 45.0 kg, whom he lifts on his shoulders. Assuming there are no external horizontal forces, what is the skater's final velocity?

14. ## Physics

What is the total charge of all the electrons in a 13 kg bar of silver? (Silver has 47 electrons per atom and an atomic mass of 108 u.)

21. ## Calc 1

A farmer with 700 ft of fencing wants to enclose a rectangular area and then divide it into four pens with fencing parallel to one side of the rectangle. What is the largest possible total area of the four pens?

22. ## physics

A 16.3 kg block is dragged over a rough, horizontal surface by a constant force of 157 N acting at an angle of 35 degree above the horizontal. Find the work done by the 157 N force.

23. ## Physics

Calculate the resistance per unit length of a nichrome wire, which has a radius of 0.436 mm. The resistivity of nichrome is 1.5×10−6 Ω·m. Answer in units of Ω/m If a potential difference of 20 V is maintained across a 3.7 m length of the nichrome

24. ## Chemistry

What is the [H3O] concentration in a 1.0M CH3COONa solution? (The Ka for CH3COONa is 2.0*10-5.)

25. ## 3 grade english

singular and plural pronouns direction revise each sentence. replace the underlined words with sigular or plural pronouns. 1- some people thought of a new sport, and the sport became popular. in this sentence the word underline is (the sport) my son write

26. ## physics

An American standard analog television picture (non-HDTV), also known as NTSC, is composed of approximately 485 horizontal lines of varying light intensity. Assume your ability to resolve the lines is limited only by the Rayleigh criterion, the pupils of

27. ## physics

The acceleration of a particle moving only on a horizontal plane is given by a= 3ti +4tj, where a is in meters per second-squared and t is in seconds. At t = 0s, the position vector r= (20.0 m)i + (40.0 m)j locates the particle, which then has the velocity

28. ## chemistry

Al(NO3)3 + NH3 --> ?

29. ## Physics

If the angle decreases what will happen to the tension? Please explain why.

30. ## chemistry

what volume does 2.5 moles of carbon monoxide occupy at 50.5 kPa pressure and 20.0 C?

31. ## Physics - Newtons laws

A block (mass m1 = 8kg) is moving on an inclined plane, coefficient of kinetic friction of 0.45, whose angle is 30degrees. This block is connected to a second block (mass m2 = 22kg) by a cord that passes over a small frictionless pulley. Find the

100. ## chemistryhelp

what does the electrolyte in batteries do?

101. ## algebra 1

(w^3-57w+43) / (w+8)

102. ## algebra

How much water should be added to 20oz of a 15% solution of alcohol to dilute it to s 10% alcohol solution?

Xy+3=x?x^3

104. ## US HIstory

In what ways was dulles's policy of brinkmanship different from truman's cold war policies? Thanks

105. ## Psychiatry

Application of psycology in developing country

106. ## english 3

11. Which one of the following statements is not true about the president Ratcliffe portrayed in The General History? He wasn't very popular. His judgment was weak in times of peril. He voluntarily turned over leadership to John Smith. He was greedy and

107. ## History

Is there any "European bias or bias" in this article? To obtain the necessaries of life, they (he Indians of Arcadia) endure cold and hunger in an extraordianry manner. During eight or ten days, if the necessity is imposed on them, they will follow the

108. ## physics

Find the acceleration of the block of mass M = 4.79 kg (m = 4.03) (KE = 0.1)

109. ## Math

A man walks one mile east, then he walks one mile northeast and then he walks one mile east. How far is he from his initial position?

110. ## PHYSICS-electricity & magnetism

An electric field exits inside a fluorescent tube of diameter 3.00cm. In one second, 2.00x10^18 electrons and 0.50x10^18 positive ions pass through a certain cross section. What is the current in the tube?

111. ## chemistry

Al(NO3)3 + NH3 --> ?

112. ## chemistry

A particular reaction has an activation energy of 51.6 kJ/mol-rxn. How much faster is the reaction at 50 degrees C versus 25 degrees C? a. 2 times b. 5 times c. 3 times d. half as fast d. 20% as fast help

113. ## physics

an 84 kg fisherman jumps for a dock into a 122 kg rowboat at rest on the westside on the dock. if the velocity of the fishermen is 4.8 m/s to the west as he leaves the dock what is the final velocity of the fishermen and the boat?

114. ## Chemistry(Please check)

1) The reaction: A + 3B = D + F was studied and the following mechanism was finally determined A+B=C (fast) C+B=D+E (slow) E+B=F (very fast) Which step has the largest activation energy? I chose the second step because it is slow and should have the most

115. ## probability problem

A box contains 6 green, 8 red, 5 yellow, and 10 blue marbles. Four marbles are drawn from the box at the same time. a) What is the probability that all four marbles are the same color? b) What is the probability that none of the marbles is blue? c) What is

116. ## math

Write expression for the other five trigonometric ratios for each acute angle: A) cscƒÆ=a/b B) secƒÀ= x+1/x-1, x‚1

one kilwatt/hour (kWh) is the amount of work or energy generated when one kilowatt of power is supplied fr a time of one hour. a kilowatt/hour is the unit of energy used by power companies when figuring your electric bill. determine the number of joules of

118. ## american history

Ineed help revising my assignment

119. ## Algebra 2

My question involves "Graphic Representation of Radicals of the Second Order" I know that the length of the hypotneuse of a right triangle equals the square root of the sum of the lengths of the two legs. The problems I'm having trouble with are the square

asked by Josh S
120. ## math

what is 9+9d=8d-12

121. ## math

The building is 16 by 12 feet so, to the nearest tenth of a foot what distance (x) fom the building should time place the 16-ft ladder so that the top of the ladder will be 12 feet above the ground?

122. ## math

antonio wants to buy a car that costs $2,500. he plans to put$400 down and pay the rest in six equal payments. find the amount of each payment

123. ## Physics - grade 11

The speed of light of a plastic is 1.4x10^8. What is the index of refraction in the plastic?

124. ## physics

What are the factors that affect the quantity of heat needed to raise the temperature of a substance?

125. ## physics

A 90 cm length of steel wire with a diameter of 0.5 mm is stretched between the inside walls of an oven the wire is just taut with no tension when the temperature in the oven is 250 °C. What is the the tension force in the wire when the oven cools to a

126. ## science

A 70 liter tank containing an ideal gas at a pressure of 40 atmospheres is connected by a valve to a 30 liter tank of an ideal gas at 70 atmospheres. The valve is opened slowly and the gases in two tanks mix. Assuming the temperature throughout is

127. ## science

A piston pump containing 2 liters of nitrogen gas at 3000 psia (absolute) pressure empties its entire contents into a 10 liter pressure container. Before the transfer of gas the 10 liter container already contained nitrogen gas at 100 psia (absolute)

128. ## math

A pie chart of total number of students in a school has a sector 35degree representing 14students.how many students are there in the school altogether?

129. ## Stem

What controls move robotic arm?

asked by Dj John
130. ## physics

If the mass of an object was 0.500 kg and it started from rest, then the object's final velocity at the end of 0.86 seconds is ?

131. ## Calculus

Evaluate the limit: lim ((7-x)^2)-9 / 4-x x->4

132. ## statistics

If the means for our groups on calories consumed a day were Group A = 2000, Group B = 2500, and Group C = 3000 could we just assume that all of the groups had statistically different means? How could we determine which groups were significantly different

133. ## math

find x such that (x,7) is 10 units from (-4,1)

134. ## Physics

Any assistance explaining how to work this would be great! The force exerted by the wind on the sails of a sailboat is Fsail = 480 N north. The water exerts a force of Fkeel = 240 N east. If the boat (including its crew) has a mass of 350 kg, what are the

135. ## math

Nick is writing the 4 letters in his name in different orders. In how many orders can he put the letters?

136. ## math

Keith, Annie, Elizabeth, and Marcus are taking a picture. How many different ways can the friends stand in a horizontal line?

137. ## US Government

What should be the goals of the US government today? I have to write an essay with this very question but I need help to formulate at least 4 different topics that the US Government should focus on.

138. ## chemistry

Explain how you would prepare a saturated aqueous solution of table sugar. Heat the solution to near its boiling point. With stirring, add table sugar to water. Keep adding sugar until no more dissolves. Allow the solution to cool. With stirring, add table

139. ## Biology

Is nail sulcus and nail fold the same thing?

140. ## books

In "Touching Spirit Bear," the book, I have to answer these questions. 1. Why does Cole think the bear attacked him? 2. In what way has Cole's mother changed? 3. What happened to Cole's dad when he was a child? 4. Who is the surprise visitor to Circle

asked by Alexis Herda
141. ## college algebra

Given f(x)= 3x^2+x-30 and g(x)=x-3 find f(x)-g(x)

142. ## physics

A 5.0 {\rm nC} point charge sits at x = 0. At the same time, a 3100 {\rm N/C} uniform electric field (created by distant source charges) points in the positive x-direction.

143. ## social studies

From the point of view of an environmentalist, which is probably the most significant argument against offshore drilling for oil?

144. ## college algebra

Given f(x)=sqrt x+4 and g(x)= 1/x find (fog)(x)

145. ## chemistry

The decomposition of hydrogen peroxide in solution and in the presence of iodide ion was studied in laboratory, and the following mechanism proposed based on the experimental data. H2O2 + I - = H2O + IO - (slow) H2O2 + IO - = H2O + O2 + I - (fast) Which

146. ## math

how do you format hours/day-percentage of time spent during an 8 hour work day ?

147. ## Calculus

find f'(x) if f(x)=x^2*e^x*(3x-1)^3

148. ## math

how many feet in a dozen

149. ## chemistry

If the reaction Cl2 (g) + O3 (g) = Cl2O (g) + O2 (g) occurred in just two steps, what would be the overall order of the reaction be? a. 1 b. 2 c. 3 d. 4 e. not possible to determine from the information given

150. ## Calculus

I could really use the help on this as soon as possible. what is the slope of the line tangent to the curve (/x)^2 at point (4,16)

asked by Jesse Stone
151. ## math

Solve variation problem if m varies jointly as z and p, and m=10 when z=2 and p=7.5, find m when z=5 and p=7

Regarding the question I posted about performance if you agree or don't agree why?

153. ## music read

After completing your study reading, it is vital that you complete which of the following steps?

154. ## Embedded Software

How would you write a linux program to read data from a joystick, and turn that data into a command that is pushed onto the queue?

155. ## math

a perso increases the number of tosses of a fair coin the actual number of heads will get farther and farther away from the number of tosses divided by 2

156. ## PHYSÝCS

At the end of the spring term, a high school physics class celebrates by shooting a bundle of exam papers into the town landfill with a homemade catapult. They aim for a point that is 31.1 m away and at the same height from which the catapult releases the

157. ## PHYSÝCS

You are walking on a moving walkway in the airport. The length of the walkway is 40.1 m. If your velocity relative to the walkway is 2.41 m/s, and the walkway moves with a velocity of 1.59 m/s, how long will it take you to reach the other end of the

158. ## PHYSÝCS

The position of a particle moving along the x-axis is given by x = 3.49t2 – 2.21t3, where x is in meters and t is in seconds. What is the position of the particle when it achieves its maximum speed in the positive x-direction?

159. ## Math

x+y=5 x-y=3 Please help me solve this system of equation and show your work thanks

160. ## criminal procedure

In which areas of search and seizure do you feel that the courts have not gone far enough? In which areas of search and seizures do you feel that the courts have not gone far enough? suport your position. Use actual court cases to support position.

161. ## Biology

Denny, who is allergic to wool, accidentally wears a scarf that is 50% wool. one hour later, after removing the scarf, she finds that the skin around her neck is red and swollen. Explain what has happened to her. (Our unit is Blood and immunity)

162. ## psychology

NREM sleep is characterized by

163. ## Statistics

For sample mean x = 150, sample size n = 36 and sample standard deviation s = 40 find 80% confidence interval for population mean. Population standard deviation is not known

164. ## CHEM

How does the neutron to proton ratio affect the stability of an atomic nucleus ?

165. ## math

The surface area of any shape is expressed in:

166. ## math

What is the surface area of a circle that has a diameter of 14 inches?

167. ## math

What is the surface area of a circle that has a diameter of 14 inches?

168. ## computer

To all computer programmer or people know or use computer programming. what tags can we use to connect the comment of the web page to your email. thanks to all of you to help me...

169. ## Calculus

what is the slope of the line tangent to the curve (/x)^2 at point (4,16) * (/x)= the squareroot of x

asked by Jesse Stone
170. ## English 3

Why are stories and poems about the "realms of darkness" so popular with many readers? Thanks -MC

171. ## Statistics

How do you find the proportion bewtween two numbers, for example, proportion of people drink between 18 and 26 gallons of water per week?

172. ## AP US History (Help Required ASAP)

Explain the rise of the republicans and the international challenges faced following world war I?

the floors in a typical house are separated by a vertical distance of approximately 8.0 ft. a teenager (1.0x 10^2 lb) climbs the stairs between floors at a steady speed. find the power necessary to accomplish this if the stairs are climbed in (a) 10.0 s

174. ## Geology

Is the distribution of geologic activity clumped, random, uniform, or some other pattern? Explain\ Is the distribution of geologic activity clumped, random, uniform, or some other pattern? Explain

175. ## physics

A horizontal wire of length 0.78 m, carrying a current of 6.8 A, is placed in a uniform external magnetic field. When the wire is horizontal, it experiences no magnetic force. When the wire is tilted upward at an angle of 20°, it experiences a magnetic

176. ## ethics

This is the question i was asked, "The things that will destroy us are: politics without principle; pleasure without conscience; wealth without work; knowledge without character; business without morality; science without humanity; and worship without

177. ## Math

john earns $10 per hour and made a total$825. How many hours did he work during this period? Write an equation to represent this situation.

178. ## BA

use scientific notation to divide the two numbers, express answer using scientific notation, retain at least 3 decimal place for (8.4.10^6)/(5.97.10^2)

179. ## physics

A car starting from rest accelerates uniformly are attaing a speed of 80m/s in 30s it maintains this stedy speed for another 30s. It then slow down uniformly until it comes to rest in the next 40s

180. ## physics

A bowling ball weighing 43.0 N initially moves at a speed of 4.90 m/s. How long must a force of 51.0 N be applied to the ball to stop it?

181. ## math

. In the annual walkathon, Lee jogs for 5 3/4 miles more than he walks. If he travelled a total of 15 miles, how many miles did he walk?

182. ## Math

y=5x-2 6x+3y=15 Please help me solve this system of equation and show your work thanks

183. ## law

• What is the role of police in society? What would happen if the role of the police were lessened as it applies to the theory and practice of community policing?