# Posts by Hannah

Total # Posts: 3,457

Spanish
I'm in the 8th grade and I have been taking French now for about a 1 1/2. I have learned many things and it is probably the easiest way to learn about another country! salut! (thats goodbye in french btw)

Chemistry
The empirical formula for Brilliant Blie dye is C37 H34 N2 O9 S3 Na2, and the formula weight is 792.86 g/mol. How would you prepare a 4.73 X 10^-6 M solution of Brilliant Blue dye? How many grams of the dye do you need to add to a 1.00 L of water to make this solution? I have ...

Chemistry
To calculate the percent error you would use the error in measurement divided by accepted value times 100 correct? So for an experiment in which you had to find the concentration of a dye in a powdered drink solution, to find the percent error would you use the number you ...

Chemistry
A sample of 30.0 mL of sulfuric acid solution was titrated with 0.720 M KOH. It was found that 46.9 mL of the base was needed to neutralize the acid. What is [H2SO4]? would you do (30.0)(0.720) / 46.9 ?

Chemistry
What volume of o.410 M HNO3 would you need to neutralize 18.75mL of 0.376M Ba(OH)2? Would you do (0.410)(18.75) / 0.376? Or (0.410)(0.376) / 18.75

Chemistry
Oh ok thank you!

Chemistry
If 7 mL of water is added to 3 mL of a 0.50 M KOH solution, the concentration of KOH is changed to? I am not sure how to go about doing this. Please help, thank you!!! Would I do (7)(3) / 0.50?

Chemistry
so would it be Mg3N2 + H2O -> 2MgOH + NH3

Chemistry
Write the balanced equation for: Magnesium nitride + water -> magnesium hydroxide + ammonia MgNO2 + H2O -> MgOH + NH3 Is this correct?

Chemistry
thank you!

Chemistry
Would this be correct for the complete equation? Ba^2+ + OH^- + H^+ + Br^- = Ba^2+ + Br^- + H2O

Chemistry
Write the net ionic equation for the reaction that occurs when aqueous solutions of barium hydroxide and hydrobromic acid are combined. I know that the first part of the formula would be BaOH + HBr but I do not know what the product would be since HBr is one thing. I do not ...

Language
What do these sets of words have in common?(Hint: Look for a sound, a keyboard, or the way they are written.) BCDEGPV QWERTYUIOP ij

Language
What do these sets of words have in common?(Hint: Look for a sound, a keyboard, or the way they are written.) BCDEGPV QWERTYUIOP ij

english
Where is pride and prejudice does mr. bennet confess that he married mrs. bennet because of her looks? a volume and chapter would be great:) I know the page numbers will be different in eat edition.

algebra
If you enter Interstate 40 at mile marker 23 in Sayre, Oklahoma, how far would you need to travel to reach mile marker 125 in El Reno, Oklahoma? After reaching El Reno, you might worry that your vehicle is running low on fuel. You know that your vehicle can travel 32 miles per...

Chemistry
is L the volume?

Chemistry
when doing a lab experiment on limiting reagents for CoCl2 there is a chart to fill out that says to find the concentration of test tubes 1-6, find the volume delivered and find the moles of CoCl2. How would I find the moles of CoCl2 for each test tube?

Thank you!

Is this equation balanced? CoCl2(aq) + Na2CO3(aq) -> CoCO3(s) + 2NaCl(aq) I think that it is because there is 1 Co on the left and 1 on the right. There is 2 cl on the left and 2 on the right. 2 Na on the left and 2 on the right and 3 CO on left and on right. Am I correct...

history
When were hunter gatherers around in america? why and when(a date or range would be great) did they settle down?

geometry
THANK YOU TCHRWILL

Chemistry, Need Help!!
a)How many grams of H2 are needed to produce 14.27 g of NH3? b)How many molecules (not moles) of NH3 are produced from 1.57×10−4 g of H2 ?

Chemistry
A)What mass of carbon dioxide is produced from the complete combustion of 7.00×10−3 g of methane? B)What mass of oxygen is needed for the complete combustion of 7.00×10−3 g of methane?

calculus
Let f(x)=6x+16x^2 . Then the equation of the tangent line to the graph of f(x) at the point (2,16) is given by y=mx+b for m= and b=

Chemistry
If the standard state of sufur is S8 (s), which of the following equations represents the standard enthalpy of formation of H2SO4 (ℓ) ?  A. 2H (g) + S (g) + 4 O (g)  H2SO4 (ℓ) B. H2 (g) + S8 (g) + 2 O2 (g)  H2SO4(ℓ) C. H2SO4 (ℓ) &#...

Chemistry
Calculate the enthalpy change, ΔrH, for the following reaction, 4 NH3 (g) + 5 O2(g) → 4 NO (g) + 6 H2O (g) given the thermochemical equations below. N2 (g) + O2 (g) → 2 NO (g) ΔrH° = +181 kJ N2 (g) + 3 H2 (g) → 2 NH3 (g) ΔrH° = ...

Chemistry
If H for the reaction I2 (s)  2I (g) is 153 kJ/mol. What is the longest wavelength of light that can break an I – I bond? In other words, what is the minimum energy, expressed in terms of wavelength, required to break one I – I bond? A. 246 nm B. 465...

What is the oxidation number of chromium in K2Cr2O7 so k=+1 (2) = 2 O=-2(7) = -14 2x + 1 +(-14) = 0 2x-12=0 x=6 so Cr is 6 Is this correct?? Thank you!!

math
are we allowed to use calculators in sat 1 math?

math
A rectangle was constructed using 24 square tiles. If you add the length and width of her rectangle together, you would get 11. What is the length and width of this rectangle?

Chemistry
What is the oxidation number of chromium in K2Cr2O7? I know that K = 1 O=-2 so 7*-2=-14 I do not know what to do now. Thank you for your help!

it is a grid 0,5.10.15,20 through 55 then it cost a camp;er 25.00 how does this work??

i need help with variables and patterns algebra

Thank you. I understand how you got the numbers for Na and H and the -6 for O but why does S have to be +4?

What is the oxidation number of sulfur (s) in NaHSO3? I know that Na is 1 but I do not know what else to do. Please explain, thank you for your help!!

Chemistry
When aqueous CuSO4 is added to aqueous Na2S2O3, why is there no reaction?

Physics
Can you explain how to figure this out? A helicoptor accelerates at a rate of 2m/s^2. If you drop a rock out of the helicoptor 3 seconds after takeoff how high is the helicoptor when the rock hits the ground. Thanks

physics
Two particles are at the same point at the same time, moving in the same direction. Par- ticle A has an initial velocity of 9 m/s and an acceleration of 2.7 m/s2. Particle B has an initial velocity of 2.9 m/s and an acceleration of 4.2 m/s2. At what time will B pass A? Answer ...

Write the balanced, complete, and net ionic equations for each precipitation reaction. 1) AgNO_3 + CoCl_2 ---> BE: AgNO_3(aq) + CoCl_2(aq) ---> AgCl_2 (aq) + Co(NO_3)(aq) CIE: Since the balanced equation is all (aq) there is no reaction so no complete or net equation. 2...

Write the balanced, complete, and net ionic equations for each precipitation reaction. 1) AgNO_3 + CoCl_2 ---> BE: AgNO_3(aq) + CoCl_2(aq) ---> AgCl_2 (aq) + Co(NO_3)(aq) CIE: Since the balanced equation is all (aq) there is no reaction so no complete or net equation. 2...

physics
A student, starting from rest, slides down a water slide. On the way down, a kinetic frictional force (a nonconservative force) acts on her. The student has a mass of 75 kg, and the height of the water slide is 11.1 m. If the kinetic frictional force does -6.8 × 103 J of...

Physics
A 49.5-g golf ball is driven from the tee with an initial speed of 41.9 m/s and rises to a height of 29.7 m. (a) Neglect air resistance and determine the kinetic energy of the ball at its highest point. (b) What is its speed when it is 5.66 m below its highest point?

Physics
A 27-kg girl is bouncing on a trampoline. During a certain interval after leaving the surface of the trampoline, her kinetic energy decreases to 150 J from 430 J. How high does she rise during this interval? Neglect air resistance.

Physics
Starting from rest, a 1.7x10-4 kg flea springs straight upward. While the flea is pushing off from the ground, the ground exerts an average upward force of 0.44 N on it. This force does 2.4x10-4 J of work on the flea. (a) What is the flea's speed when it leaves the ground...

Physics
A person pushes a 23.4-kg shopping cart at a constant velocity for a distance of 31.1 m on a flat horizontal surface. She pushes in a direction 34.8 ° below the horizontal. A 38.5-N frictional force opposes the motion of the cart. (a) What is the magnitude of the force ...

A piece of copper contains 3.6 x 10^8 atoms. What is the volume of the sample in units of liters? i have no idea how to start this. Please help thank you!!!

Calculus
2sin(2theta) + sqrt(3) = 0 interval (0,2pi) How do I solve this? I thought about maybe subtracting the sqrt(3) from both sides, so that i would have 2sin(2theta) = -sqrt(3) Then maybe dividing by two? sin(2theta) = -sqrt(3)/2 Am I doing anything right here? It's been a ...

chemistry
If you dissolve 29.25 g of sodium chloride in 250 g of H2O. What would be the freezing point? Kfp- -1.86 degrees C/molal I know the formula is K times molality. I am taking -1.86(2.00) and getting -3.72 degrees Celsius, when the answer is -7.44 degrees. What am I doing wrong?

Science
Unscramble acnsrl spgei

A piece of copper contains 3.6 x 10^8 atoms. What is the volume of the sample in units of liters? I know that first you have to get atoms to cancel out but them I do not know what to do!

physics
A 0.07 kg toy is made up of a spring of constant 375 N/m. When you place the toy on the floor, cock the spring 7 cm and release it, the toy jumps upwards. What is in Joules the mechanical energy of the toy when sitting on the floor with a cocked spring? Use 10 m/s2 for g.

physics
A 0.05 kg toy is made up of a spring of constant 466 N/m. When you place the toy on the floor, cock the spring 5 cm and release it, the toy jumps upwards. What is in Joules the spring potential energy stored in the toy when sitting on the floor with a cocked spring? Use 10 m/...

physics
A 0.05 kg toy is made up of a spring of constant 466 N/m. When you place the toy on the floor, cock the spring 5 cm and release it, the toy jumps upwards. What is in Joules the spring potential energy stored in the toy when sitting on the floor with a cocked spring? Use 10 m/...

physics
It takes 9.10 J of work to stretch a spring 5.10 cm from its unstressed length. What is the spring constant k in N/m?

physics
It takes 5.50 J of work to stretch a spring 5.90 cm from its unstressed length. What is the spring constant k in N/m?

physics
Amy threw a ball of mass m=0.79 kg horizontally with an initial velocity v=33.4 m/s from a height h=1.9 m. What is the kinetic energy of the ball just before it touches the ground? Express your answer in Joules and use 10 m/s2 for g.

physics
A 0.730 kg particle has a speed of 3.00 m/s at point A and kinetic energy of 7.40 J at B. What is its speed at B? Answer in units of m/s.

physics
A 4.62 x 10-5 kg raindrop falls vertically at constant speed under the influence of gravity and air resistance. After the drop has fallen 83.7 m, what is the work done by gravity? Answer in units of milliJoule (a thousandth of a Joule) and use 9.8 m/s2 for g

geography
As population goes up food levels are being consumed too fast and so the food level will go down

physics
i am confius too why nobody answer this question?

A piece of copper contains 3.6 x 10^8 atoms. What is the volume of the sample in units of liters? I know that first you have to get atoms to cancel out but them I do not know what to do.

A piece of copper contains 3.6 x 10^8 atoms. What is the volume of the sample in units of liters? I know that first you have to get atoms to cancel out but them I do not know what to do.

scientific method and measurement 8th Hons science
You see i already know its not replicable or such 13 letters long and it ends with an N.

scientific method and measurement 8th Hons science

scientific method and measurement 8th Hons science
what allows results to be verified to maintain credibility?

The radius of a niobium atom is 131 pm. How many niobium atoms would have to be laid side by side to span a distance of 1.4 mm?? I know that 10^9 is pm or is it -9??

Math
4.47 x 10^1 g How wouldI convert this to nanmograms? would I use 1mg / 10^-9 g? I do not understand how to do this

math
8 decimeters

metric system conversions 1)3.68kg = ? g (3.68 kg) (10^-3 / 1kg) = 3.68 x 10^-2 g 2) 568cm = ? m (568cm) (1 m /100cm) = 5.68 m Are these correct?

PHYSICS
A student of weight 830 N was sent to another planet called Nerdland. If Nerdland has a mass that is three times the mass of the earth and a radius that is half the radius of the earth, what would be the mass in kg of the student when on Nerdland?

Calculus
find f(3) and f'(3), assuming that the tangent line to y=f(x) at a=3 has the equation y=5x+2.

Physics
At the heighest point on earth, the distance to the center of the earth is approximately equal to 1.0014 times the radius of the earth. What would be in N/kg the magnitude of the gravitational field (g) due to the earth at that position? Assume 9.8 N/kg for g at the surface of...

pre cal
A movie theater seats 400 people. For any particular show, the amount of money the theater makes is a function m(n) of the number of people, n, in attendance. If a ticket costs 2 dollars, find the domain and range of this function

Math
An auditorium has 1600 seats. At a ticket price of \$6, the owners can sell 1200 tickets. For each 25 cent increase in price the tickets sold reduces by 25. What price should the owners set to maximize the income?

Math
What is another name for odd numbers?

Why are cyanobacteria not bacteria? Is it because they can be nitrogen fixers?

Math
The expression 9a + 6s is theh cost for a adults and s students to see a musical performance.

physics
A body moving with uniform acceleration has a velocity of 9.9 cm/s when its x coordinate is 1.28 cm. If its x coordinate 1.3 s later is -9.1 cm, what is the magnitude of its acceleration? Answer in units of cm/s2.

physics
An electron has an initial speed of 178000 m/s. If it undergoes an acceleration of 4.8 x 1014 m/s2, how far has it traveled before reaching a speed of 789000 m/s? Answer in units of m.

physics
An electron has an initial speed of 178000 m/s. If it undergoes an acceleration of 4.8 x 1014 m/s2, how far has it traveled before reaching a speed of 789000 m/s? Answer in units of m.

Speech
I have to give a speech soon about my different " sides" of my life. Like my school life and what I do at school compared to how I act as a sibling etc. But I'm stumped on what my visual should be. My teacher wants originality no power point or posters with just ...

Pre-Algebra
5 and 17/20 - 3 and 1/4

Pre-Algebra
5 and 17/20 - 3 and 1/4

math
Suppose f is a 1-1 function with domain A and range B. What is the range of f^-1? Would it be A?

math
1.)P -< \$10.00 2.)P=\$12.98 -< \$10.00

introductory technology
A boat is tied to a stake on a fast flowing river. What energy does the boat gain when the rope is cut.

the setting where does the story take place, time period (present, future etc.), the main character(s), the plot-what happens to the main character

I need help on writing a book report on anastasia absolutely

t-test for independent means: n=8 t=-1.33 df= 8 C.V. = plus or minus 2.306 My question is how do you get 2.306 for the cv??? Why wouldnt the cv be 2.31?

statistics
t-test for independent means: n=8 t=-1.33 df= 8 C.V. = plus or minus 2.306 My question is how do you get 2.306 for the cv???

Chemisty
How would you classify a solution of NaCl at 35.9 g/100 g of water at 20° C?

Chemisty
that's all the information i have, this is my only worksheet on the subject so i'm honestly only looking for an answer

Chemisty
How much KNO3 will you have to add to 100 g of water at 40° C to make a saturated solution?

Chemisty
In terms of saturation, how would you classify a KBr solution with a concentration of 78 g/100 g of water at 47°C?

Chemisty
In terms of saturation, how would you classify a KBr solution with a concentration of 78 g/100 g of water at 47°C?

Prob ans stat
Let x be a random variable that represents the length of time it takes a student to complete a take-home exam in Dr. Larson's psychology class. After interviewing many students, it was found that x has an approximately normal distribution with mean of 5.2 hours and ...