# Posts by Alex

Total # Posts: 3,844

CHEMISTRY !!! HELP !
K1*K2=(x^2*.0226)/.0158=.0000671 Which results in pH being 4.17 But it seems that my answer is still wrong. An i missing something ?

CHEMISTRY !!! HELP !
I tried with both of them but the answer was still wrong.

CHEMISTRY !!! HELP !
A solution containing 0.0158 M maleic acid and 0.0226 M disodium maleate. The Ka values for maleic acid are 1.20 × 10-2 (Ka1) and 5.37 × 10-7 (Ka2). What is the pH of the solution ?

Chemistry 101
I'm not sure but isn't there supposed to be specific heat involved in there ? (Sorry if it's a silly question, but i'm still a high school student)

Chemistry
A solution containing 0.0158 M maleic acid and 0.0226 M disodium maleate. The Ka values for maleic acid are 1.20 × 10-2 (Ka1) and 5.37 × 10-7 (Ka2). What is the pH of the solution ?

chemistry
I'm just an ordinary student like you so I might be wrong but it's H2O x Specific heat(2.09 J/g⋅C) x delta T x stands for multiplication and delta T is change in temperature

Math
I believe that is the correct answer

Physics
A Formula 1 car it heading for a straight piece of track which is 500m long. He is travelling at 220km/h. How long will he take to cover this amount of track? Time = Distance / Speed I'm confused as I don't know whether to change the distance to equal the speed's ...

Geometry
A design on the surface of a balloon is 5 cm wide when the balloon holds 71 cm of air. How much air does the balloon hold when the design is 10 cm wide? Explain the method you use to find the amount of air.

Geometry
The equation (x + 5) + (y + 3) = 169 models the position and range of the source of a radio signal. Describe the position of the source and the range of the signals.

Math
The equation (x + 5) + (y + 3) = 169 models the position and range of the source of a radio signal. Describe the position of the source and the range of the signals. How would I explain it?

History
Suspicion had always troubled the relationship between the Western powers and the Soviets. The Soviets didn't trust the West in anything, especially Stalin, though he gave them reasons that they couldn't trust him, either, when his armies began gobbling up Eastern ...

History
What factors led the wartime alliance between the United States and the Soviet Union to disintegrate into the Cold War? What would be a great short answer?

Chemistry
When 1.63 g sample of an unknown hydrocarbon is completely burned in oxygen, 4.97 g of CO2 are produced. What is the percentage by mass of hydrogen in this hydrocarbon? THANK YOUU Found out the formula: 4CH+5O2--> 4CO2+2H2O then found out the moles of CH= 0.1251 I don't...

PHYISCS
-90.16

Cemistry
refrigerator and window

Math
At a track meet, 50 people ran the 100-meter dash. 2 people finished in 11 seconds, 5 people finished in 12 seconds, 8 people finished in 13 seconds, 10 people finished in 14 seconds, 21 people finished in 15 seconds, 2 people finished in 16 seconds, and 2 people finished in ...

Math
Janine wants to paint just the sides of a cylindrical pottery vase that has a height of 45 cm and a diameter of 14 cm. To the nearest whole number, find the number of square centimeters she will need to paint. Explain the method you would use to find the lateral area.

Math
An hourglass, composed of two identical cones, is 12 cm tall. The radius of each cone is 3 cm. If you want to fill the bottom half of the hourglass full of salt, how much salt will you need? Explain the method you would use to find the amount of salt.

Chemistry
Calculate the number of moles of carbon atoms present in 2.2 g of ethanol (C2H6O). For this question, I would just need to find the molar mass of carbon, right? Not the molar mass of all of ethanol? So it would just be 2.2 g/ 24.02 g/mol which would equal .092. It wouldn't...

Write an expression for the distance a car travels in t hours at a speed of s km/h

Bio
12

Physics
A person exerts a force of 90 N on a rope that pulls a sled across a very smooth surface. The rope is oriented 37∘ above the horizontal. The sled has a total mass of 40 kg . The sled starts at rest and moves for 10 m.

Physics-Trajectory
x =(1/2t^3?2t^2)m and y =(1/2t^2?2t)m

Physics-Trajectory
B. 17.75 Because sqrt([3/ 2 t^2 - 4t]^2 + [t - 2]^2).

Physics-Trajectory
A. v=2m/s C. -90

ap calculus
((1/-2-h)-1)/h

Math
if a bullet travels at 645.0m/s, what is its speed in miles per hour? can you please show me how to solve this?

Chemistry
Round each number to two significant figures: 233.356 0.002353 1.005 Can you please show me and explain how to do this? Im confused. thank you!!!

Math
A triangle has side lengths 10, 15, and 7. Is the triangle acute, obtuse, or right? Show your work and explain. I think it's gonna be an obtuse and maybe right....might be wrong...

Chemistry
Hi! I really really need help in this question: what observation is expected when: 1. an acid (nitric acid, HNO3) is added to a solution containing carbonate or bicarbonate ions? 2. silver ion is added to a solution containing chloride (or bromide or iodide) ions? Please help ...

probability
thanks Reiny, the buttons were pushed

probability
Two hunters shoot at the same duck. The probability of the first hunter hitting the duck is 0.2. The probability of the second hunter hitting the duck is 0.75. Hitting the duck results in its death. What is the probability of the duck being killed?

probability
A survey asks people about their reading habits with respect to three newspapers. The results show that 56% read newspaper A, 33% read newspaper B, and 27% read newspapers C. 7% of the respondents read newspapers A and B, 8% of the respondents read newspapers B and C, 11% of ...

Hi! I really really need help in this question: what observation is expected when: 1. an acid (nitric acid, HNO3) is added to a solution containing carbonate or bicarbonate ions? 2. silver ion is added to a solution containing chloride (or bromide or iodide) ions? Please help ...

CHEMISTRY
i meant Pb304…sorry, my mistake

microeconomics
Budget constraint 1 is faced when price food = 10 and price clothing = 5. Budget constraint 2 is faced when pfood = 40/7 and pclothing = 10. The income is 100 for both budget constraints. Draw both budget constraints. Next, draw the following four consumption bundles in your ...

English: Amoretti LXXV: One Day I Wrote Her Name
What are three questions asked in this sonnet. If you can help great! If not that's fine

physics
A tourist being chased by an angry bear is running in a straight line toward his car at a speed of 4.09 m/s. The car is a distance d away. The bear is 20.9 m behind the tourist and running at 6.04 m/s. The tourist reaches the car safely. What is the maximum possible value for ...

microeconomics
Save Open Spaces (SOS) is a non-profit organization that promotes protection of undeveloped land. They perform two primary activities: purchasing undeveloped land for preservation and lobbying Congress for additional protection for undeveloped land. SOS has a budget of \$600,...

microeconomics
Mickey is very picky and insists that his mom makes his breakfast with equal parts of cereal and apple juice. Any other combination ends up on the floor. Cereal costs 4 cents per tablespoon and apple juice costs 6 cents per tablespoon. If his mom budgets \$8 per month for his ...

Physics
In a cathode ray tube, a beam of electrons is injected horizontally into the exact center of the parallel-plate region. Here L = 3.0 cm and d = 0.20 cm. The top plate has a surface charge density of σ0 = +0.15 μC / m2, and the bottom plate has a surface charge ...

Physics
Inside a metal conductor, why is it not possible to have a static charge configuration if there is a net electric field?

american history
That link doesn't have a specific site ...it brings out google ...

american history
Did the Watergate scandal have any lasting effects on the nation? Explain.

american history
What factors led the wartime alliance between the United States and the Soviet Union to disintegrate into the Cold War?

american history
What were the key aspects of Lyndon B. Johnson’s Great Society?

american history
What factors led the wartime alliance between the United States and the Soviet Union to disintegrate into the Cold War?

american history
How did the New Deal affect women, African Americans, and Native Americans?

american history
What were the causes of World War I?

Math
If Ms. Herbert gives her class a English quiz every 6 days any math quiz every 10 days when is the first day there will be a math and English quiz on the same day

american history
What was factory work like in the late 1800's?

american history
How did the spoils system affect politics during the Gilded Age?

american history
I'm still confused

american history
In the 1812-1860

american history
What arguments did supporters of the public school movement make to support their cause?

american history
Why did so many colonists protest the Stamp Act?

Chemistry
90.74

Chemistry
In chemical analysis, it is often necessary to prepare a solution by diluting a stock solution.Calculate how much of a 5.337M NaOH is needed to make 1.669 liters of a 0.063M sodium hydroxide solution. (Remember to include units.)

Chemistry
To determine the concentration of 10.31mL of an unknown solution of a monoprotic acid, it is titrated with 0.172M sodium hydroxide. The initial reading on the buret of sodium hydroxide is 2.19mL. The final reading is 13.41mL. What is the concentration of the unknown acid?

Social studies
Mayan priests interest in astronomy led to the creation of ____. A. a 365-day calendar B. A book of rules C. Human sacrifices D. Cave paintings Which one is correct ? Please help

Physics
19. A track consists of a frictionless incline plane, which is a height of 0.5 m, and a rough horizontal section with a coefficient of kinetic friction 0.02. Block A, whose mass is1.5 kg, is released from the top of the incline plane, slides down and collides instantaneously ...

Algebra
You invested 20,000 in two accounts paying 4% and 7% annual interest, respectively. If the total interested earned for the year was \$830, how much was invested at each rate?

Art
Would it be space?

Art
1. In the image, Green Wheat Fields, Auvers by Vincent van Gogh, which of the following elements was not used to create the principle of harmony? A. Colors B. Form C. Line D. Texture 3. In the image, The Annunciation, by Jan van Eyck, which element in this image creates ...

pre-calculus urgent
Please help me here as well to clarify more my understanding. Let a1, a2, a3, . . . be a geometric sequence with initial term a and common ratio r. Show that a1^2, a2^2, a3^2, . . . is also a geometric sequence by finding its common ratio. Given that the ratio for a1, a2, a3...

pre-calculus urgent
The first term of an arithmetic sequence is 6, and the tenth term is 2. (a) Find the common difference d. d = Find the 100th term of the sequence. a100 = (b) Find the partial sum of the first ten terms. S10 = how do i do this, there's an example I tried following but it ...

Math
Drew is twice as old as his sister joy.The quotient of their ages five years ago is seven less than Joy's present age. Find out how old they are at present.

Algebra
m+7/m^2+4m-21

Chemistry
Why is the rate determining step the slowest step?

American History
What caused the King Philip's war? Can you briefly explain or send me some links to sites.

Unions have a substantial impact on the compensation and work lives of both unionized and non-unionized workers. Unions raise wages of unionized workers by roughly 20% and raise compensation, including both wages and benefits, by about 28%. Unions reduce wage inequality ...

personal finance
You purchase a car \$22,000. The interest rate is 5% and you decide to pay over a period of 5 years. What is your payment?

physics
You push against a steamer trunk at an angle of 33° with the horizontal . The trunk is on a flat floor and the coefficient of static friction between the trunk and floor is 0.55. The mass of the trunk is 43 kg. What is the minimum magnitude of force that will allow you to ...

Public speaking
Saying "gonna" instead of "going to" is an issue of: A. Body movement B. Eye contact C. Articulation D. Timing

Physics
A projectile of mass 0.636 kg is shot from a cannon, at height 6.6 m, as shown in the figure, with an initial velocity vi having a horizontal component of 6.8 m/s. The projectile rises to a maximum height of ∆y above the end of the cannon’s barrel and strikes the ...

Physics
Three blocks of mass 10kg, 20kg, 15kg respectively are being pushed in a row on along a horizontal surface with constant velocity by a force applied to the 10kg block.The coefficient of kinetic friction between each of the blocks and the surface is 0.18. What is the magnitude ...

physics
A jetliner is traveling east from Seattle to Chicago, a distance of 1,750 miles. The jetliner travels at an average air speed of 620 mph relative to the air. At the jetliner's altitude, the wind is blowing 46 mph to the east. How long does the journey take?

physics
An astronaut in a spacecraft looks out her window and observes a comet travel in the opposite direction at a relative speed of 237 m/s. The velocity of the spacecraft is 114 m/s directly away from the sun. What is the comet's velocity relative to the sun? Assume that ...

physics
A stone is thrown vertically upwards, reaches a highest point, and returns to the ground. When the stone is at the top of its path, its acceleration

physics
Hot air balloon A is rising upward a rate of 5.0 m/s. A passenger aboard balloon A observes balloon B rising upward at a relative rate of 7.5 m/s. What is the velocity of balloon B relative to the ground? Assume that up is positive.

physics
A test rocket is fired straight up from rest. The net acceleration is 20 m/s2 upward and continues for 4.0 seconds, at which time the rocket engines cease firing. What maximum elevation does the rocket reach?

Calculus
So don't write cos x = 0 and sin x = 0 ?

Calculus
Okay

Calculus
Yes, so what work do I need to show how I got a Absolute Maximum at pi/2 and 3pi/2

Calculus
To show how I got the answer, is the work sufficient? f(x)= sin^2(x) f'(x)=2sinx(cosx) = cosx(2sinx) cosx=0 sinx=0 f(0)=0 f(pi)=0 f(pi/2)=1 f(3pi/2)=1 Absolute Maximum is at pi/2 and 3pi/2

Calculus
On the closed interval, [0, 2*pi], find the absolute maximum of the function f(x)= sin^2(x)

Calculus
-3/2 feet per minute I meant

Calculus
Is this right? 1.5 ft = dr/dt 2x dx/dt + 2y dy/dt = 0 2(18)(2) + 2(24)= 0 72 + 48 dy/dt = 0 48 dy/dt = -72 dy/dt = -72/48 = -3/4 feet per minute

Calculus
36 dx/dt + 48 dy/dt = 0 48 dy/dt = -36 dx/dt dy/dt = -.75 or -3/4

Calculus
So what's next to find the rate at which the ladder is moving toward the building when it is 18 ft from the wall?

Calculus
A ladder 30 ft. long is leaning up against a building. If the top of the ladder is being pulled up the wall of the building at a rate of 1.5 feet per minute, find the rate at which the base of the ladder is moving toward the building when it is 18 feet from the wall.

French, foreign languages
Hi the following sentences are basically unscrambling them in the first place and then putting the sentence in order. If when looking through my unscrambled sentences and you see something wrong with the grammar or something of that nature that does not make the sentence ...

French, foreign languages
Hi, This are my answers using verbs from a list provided in the assignment in the future. If something within the sentences or if I have used a verb wrong please let me know and if possible tell me a correction I can make to make it more understandable or more grammatically ...

French, foreign languages
I need help understanding the present subjunctive in French and also the usage of Il faut in said sentence

Math
Byron’s house has a roof with dimensions shown. (Roof: 1m Height, 7m Hypotenuses, 12m length) He knows that the average rainfall in his suburb is 30cm per year. Byron would like to install a cylindrical rainwater tank to hold the water that runs off the roof. The tank is ...

French, foreign languages
I need help completing an assignment that includes completing sentences from a reading. T The questions have my answers within them to complete the sentence. Once you have read the the questions with my answers within the questions and you see something wrong with my answers ...

MWS
well then that can be the answer thxs

MWS
First i thought it was new companies and now i have second thought i think it is now trade organizations what do you think

MWS
In recent times, Latin American countries have tried to improve their economies by forming these. Need help