# Posts by maddy

Total # Posts: 179

**pre-algebra**

The sum of two numbers is 31. The first number is 5 less than the second. Find the numbers. what?

**Chem**

If 25.0 cm3 of 0.50M sulfuric acid reacted with exactly 12.5 cm3 of sodium hydroxide, calculate the concentration of the alkali. I first balanced the chemical equation between sulfuric acid and sodium hydroxide. H2SO4 + 2NaOH --> 2H2O + Na2SO4 I converted the volume of ...

**Chem**

If 15.0 cm3 of 2M hydrochloric acid reacted exactly with 40.0 cm3 of potassium hydroxide. Calculate the concentration of the alkali I got the answer of .75M for KOH I went from cm^3 of HCl to L to mols then mols of KOH then to molarity of KOH. Is this correct?

**Chem**

What mass of precipitate is produced when 40.0 mL 0.100M lead nitrate reacts with 30.0 mL 0.100M aluminum sulfate? Assume the volumes are additive. I keep getting the answer of 2.7g precipitate formed rather than the answer of 1.21g. I am using an ice table and find that the ...

**Math**

Bart and Bethany play a game. They each roll a regular 6-sided die labeled 1to 6. Use an outcome table to show all possible outcomes: (2 marks) is the total number of outcomes 12?

**History**

It's A

**Chemistry**

Solid CuCl2 is 2.03g Fe before reaction reaction 2.0072g Decrease in nail mass 0.32239

**Chemistry**

Assume that the reaction was limited by the surface area of the nails, making Fe the limiting reactant. Based on the decrease in the mass of nails, calculate theoretical yield of copper. 2Fe+3CuCl2--->2FeCl2+3Cu

**Calculus**

I cannot figure out how to simplify this.

**Calculus**

find the intervals on which f is increasing and decreasing f(x)=(x-2)/(X^2-x+1)^2 I found the derivative a got a whole mess of things: ((x^2-x+1)^2-2(x^2-x+1)(2x-1)(x-2))/(x^2-x+1)^4 Do I have to use the quadratic formula to solve for the vertices to find where it is ...

**Chemistry**

Prepare 30mL of a stock KI soln by mixing 10.0mL of the 0.03M KI in 0.2M KNO3 with 20.0mL of the .2M KNO3 Determine the concentration of the iodide ion. What does it mean by the 0.03M KI in 0.2M KNO3? Is this just bad wording of the question? Am I just mixing the 10.0mL of ....

**Chemistry**

A student prepares a soln that is initally 0.006M Pb2+ and 0.00450M I-. This soln is placed into a 1.00cm wide cuvet and inserted into the spectrometer producing as abosrbance reading of 0.430 at a wavelength of 456nm. What is the equilibrium concentration of the iodide ions ...

**Chemistry**

20.02

**Chemistry**

If the concentration of KCN at the equivalence point is 0.1M and the Ka for HCN is 6.2*10^-10 find the pH at the equivalence point. The reaction is between KOH and HCN From my understanding I have to do a stoichiometric calculation and then use the Henderson-Hasselback ...

**Government**

I got Smart's test and got 100%

**Math**

How many 2's must be multiplied together for the product to be a number between 100 and 200?

**Geometry**

The formula for area of a square is a^2. The find the length of a side reverse the formula by finding the square root of 196.

**science**

Can somebody help me understand batteries? I'll explain what I know, then, you can tell me if I'm right or wrong. I know that a battery consists of three main parts: the anode, the cathode, and an electrolyte. The anode is electropositive and the cathode is ...

**Chemistry**

-14.5

**Social Studies**

I NEED THE ANSWER!!!!!!!!!PLEASE!!!!!!! I WILL FAIL MY TEST!!!!!!!!

**Chemistry**

How many grams of NaNO2 must be added to 1 liter of 1.00 M HNO2 solution in order to prepare a buffer solution with pH = 4.14? pH = 3.14? My work: ka = pH(buffer ratio) 4.5 * 10^-4 = 1.000*10^-4.14 (x M of base/1.00 M of acid) x = 6.21 6.21 M = (6.21 moles/1 L)(1 L) = 6.21 ...

**Physics**

A 35 micro coulomb point charge is placed 32 cm from an identical 35 micro coulomb charge. How much work would be required to move a 0.5 micro coullomb test charge from a point midway between them to a point 12 cm closer to either of the charges?

**Physics**

A large statue in a crate is being moved. The mass of the statue and the crate is 150 kg. As the statue slides down a ramp inclined at 40.0°, the curator pushes up, parallel to the ramp’s surface, so that the crate does not accelerate. If the statue slides 3 m down ...

**Math**

it would be 111164774.000000001

**science**

a

**PreCalc**

Sqrt of 9sin^2x Is the answer |3sinx|? Is the three included in the absolute value sign? My teacher is very picky and I need to fully understand this concept. Thank you.

**PreCalc**

Graph y=2csc(x-π) New period that I solve for 0<x-π<2π π<x<3π What is my quarter period? I got that it was 3π/4 but when I add this to pi 4 times o reach 4π instead of 3π. Please help.

**Math**

3/32

**Algebra**

Factor: x^4(4) (2x+1)^3 (2x)+(2x+1)^4 (4x^3) Please help! I cannot figure out how to go about this problem

**SOLVED**

I figured it out after staring at what steps I already had written down.

**Algebra**

Rationalize the denominator. The twos are outside of the square root signs. 5/(sqrt14)-2 x (sqrt14)+2/(sqrt14)+2 The answer is sqrt14+2/2 I am having trouible understanding hoe to get rid of the 5

**Algebra 2**

Which of the following equations represents the line that is parallel to the line y=5x+2 and that passes through the point (1,-3)?

**Physics**

Two tuning forks are struck at the same time; one with a pitch of 410Hz one a frequency of 500Hz. How many pitches do you hear and what are the frequencies?

**Social Studies**

I have no clue...

**Social Studies**

Read the passage and answer the question that follows: John Brown, supported by abolitionists and Republicans, tried to start a slave revolt. Therefore be it resolved that the defense of slavery is a common cause to all Southern states. At the call of any Southern state, we ...

**Chemistry**

The volume of the nitrogen gas is 125ml atmospheric pressure is 763mm Hg Water temperature is 24 degrees Celcius. The water level inside the eudiometer is the same as the level of water in the beaker. Calculate the pressure of the dry nitrogen gas. PH2=Ptotal-PH2O PH2=763 mm ...

**Chem**

I got the answer 1.125grams. Please help!

**Chem**

If a .750g sample of magnesium chloride is dissolved in water and then treated with a silver nitrate solution how many grams of silver chloride should be collected? I don't understand what my first step should be. The balanced equation is MgCl2+2AgNO3=2AgCl+Mg (NO3)2 Do I ...

**us history**

Was it right?

**chemistry**

8.778 KJ/Mole

**Math**

Fin the value of Theta if sec theta=3 I inverted the value of sec theta to get cos theta=1/3 I then said Theta=cos-1 (1/3) Is thus correct? What is the answer rounded to the tenths place?

**Trigonometry**

Find cotangent theta given that cosecant theta equals -3.5891420 and theta is in the third quadrant. I was using the trig identity 1+cot^2theta=csc^2theta I wanted to isolate cotangent so I plugged in 1/sin (-3.5891420) and then squared my answer. I then subtracted one from ...

**Chemistry**

32.0=5.5x10^2(1/T)+14.2 Solve for T I am confused about what the first step would be to solving for T. Would I divide 5.5x10^2(1/T) and move it to the left side? Please help.

**Algebra**

32.0=5.5x10^2(1/T)+14.2 Solve for T I am confused about what the first step would be to solving for T. Would I divide 5.5x10^2(1/T) and move it to the left side? Please help.

**Algebra**

Can you please help me solve r1/r2 = sqrt(M2/M1)for M1. My answer: M1=M2r2^2/r1^2 Is this correct?

**Science-Chemistry**

Thank you very much DrBob222

**Science-Chemistry**

Can you please help me solve r1/r2 = sqrt(M2/M1)for M1. My answer: M1=M2r2^2/r1^2 Is this correct?

**Chemistry**

Can you please help me solve r1/r2 = sqrt(M2/M1)for M1. My answer: M1=M2r2^2/r1^2 Is this correct?

**science**

i need help with more questions in the packet heres my question the poisonous gas hydrogen sulfide, H2S, can be neutralized with a base such as sodium hydroxide, NaOH. THE unbalanced equation for this reaction follows: NaOH(aq)+H2S(g)→Na2S(aq)+H2O(l) a student who was ...

**science**

i need help with a packet that im struggling with my questions are write the total number of atoms present for the following questions: a. 4SO2 now i tried and got 8O'S and 1S b. 8O2 i tried and got 16 all together c. 3Al2(SO4)3 i tried and got 6Al, 3S, and 12O my next ...

**chemistry**

i have a homework packet that i am struggling with can you please help me my first question is i have to finish the following equation to balance it out my question is 3Fe3O4+blankAl→blankAl2O3+blankFe now i tried and i got 3Fe3O4+2A=2Al2O3+2Fe i don't know if that&#...

**physics**

Doesn't that just give me back my original equation of mgy=kx^2?

**physics**

I need some help with determining the equation for this problem. "The block of mass m is released from rest on the frictionless incline. After sliding a certain distance, it compresses a spring and comes to rest at a distance of y beneath its original position. How much ...

**Chemistry**

2.59 Degrees

**social (fifth grade)**

on the internet

**Math**

no anna was right I got 5/5 %100

**Chemistry**

3p orbitals 2sp and 2p orbitals 6sp3d2 orbitals

**Algebra**

Thank you sooo much!!!

**Math**

Jason Printing has $85,000 to invest. They can invest in Wilder Revenue at 10% compounded semiannually or at Cheapskate Investments at 9.8% compounded monthly. a) Calculate the two APYs and compare them to determine your answer. Make sure to distinguish which APY belongs to ...

**Math**

Jason Printing has $85,000 to invest. They can invest in Wilder Revenue at 10% compounded semiannually or at Cheapskate Investments at 9.8% compounded monthly. a. Calculate the two APYs and compare them to determine your answer. Make sure to distinguish which APY belongs to ...

**Chemistry**

oooo DrBob getting savage haha

**algebra**

Show all steps, combine like terms what is a simple form of the expression-3(-4y+3)+7y

**algebra**

Solve the compound inequality-2<2x-4<4 answers are 0<x<-2,, 1<x<4, 1<x<0,, 3<x<6

**algebra**

Name the property of real numbers illustrated by the equation 2·(8·7)=(2·8)·7 answers are. Distributive property ,associative property multiplication, Communicative property multiplication, Associative property addition

**PreCalc**

stacey is standing 5 miles west of the control tower at an airport. A plane took off traveling directly north of the control tower at a rate of 180 mph along the ground at a constant angle of 15 degrees. A)after 12 minutes, what is the angel between Stacey and the plane along ...

**math**

WHAT no that is so inappropriate plus cant you get band from this sight

**Calculus!!!**

A piece of wire 28 m long is cut into two pieces. One piece is bent into a square and the other is bent into a circle. (a) How much wire should be used for the square in order to maximize the total area? (b) How much wire should be used for the square in order to minimize the ...

**Maths**

Hi I have a maths problem I can't figure out please someone help. Zac had some 2c stamps and 5c stamps.he needed to put 30c on a postcard to mail it.what combinations of stamps could he use.

**physics**

An oven is plugged into a 120 V electrical outlet and "cooks" the food by using a 144 ohm resistor light bulb that converts electrical energy to both light and heat energy. If the light bulb converts 75% of the electrical energy to thermal energy, and the oven is ...

**physics**

A 5.0 ball is initially sitting at rest on top of a 41 m high hill. The ball is pushed with a force of 25 N for 3.0 s toward the edge of a hill. Upon reaching the edge, the ball is allowed to roll down the hill where it reaches the flat ground. To the nearest mile per hour, ...

**algebra 2**

two resistors are connected in parallel. their resistances are 8 ohms and 17ohms. what is the resistance of the combonation.

**algebra 2**

if a rock is dropped from the top of a 200 ft building, solve for the time it takes for it to hit the ground. (when h=0) hint-initial velocity when dropped is 0

**Math- Precalculus**

Write the expression as the sine, cosine, tangent of an angle (in radians.) (tan(pi/5)-tan(pi/3))/(1+tan(pi/5)tan(pi/3))

**Math**

help please lol.

**Math**

Solve. 10/3x + 4/3 = 7 + x/2x A) x = 1/3 B) x = 17/5x C) x = 1/5 D) x = 1/6 thinking it's A.. help?(:

**Math**

Solve. x+12/x+4 = x/x+8 A) x=-4 B) x=8 C) x=6 D) x=-6 thinking that it's B.. help?(:

**Physics**

Thank you!

**Physics**

Two resistors 3 Ù and 6 Ù are connected in parallel across a 6 V battery. What is the current flow through the 3 Ù resistor?

**Algebra 1**

What is 5x cubed over x squared multiplied by 3x to the fourth power over 6x?

**math**

A pair of dice is rolled once. suppose you lose $9 if the dice sum to 9 and win $11 if the dice sum to 4 or 6. how much should you win or lose if any other number turns up in order for the game to be fair?

**statistics**

How do you calculate the degrees of freedom for unequal sample sizes and unequal variance (independent t test)

**Predicate and subjects**

1. The smell of cooking is delicious to the hungry camper. 2. A good fire is difficult to build. looking for simple subject and predicate 1, smell. Predicate. Camper subject 2. Fire subject. Build predicate

**chemistry**

A reaction has ÄH = -378 kJ and ÄS = -37 J/K. Calculate ÄG at 25°C to confirm that the reaction is spontaneous. in kJ

**chemistry**

4 FeO(s) + O2(g) ¨ 2 Fe2O3(s) calculate value of delta H i have done this 4(-272.0)+0->2(-825.5) and the products minus reactants and i got -563 but it is not right?!

**chemistry**

thanks helped with a different question

**chemistry**

nevermind i found it -687

**chemistry**

on my selected thermodynamic data i cant find delta H for SiCl4(L) (i can solve the reaction i just cant figure out what SiCl4(L) is.

**chemistry**

EXTRA CREDIT QUESTION(this is like kinda really hard for me at the moment i got the first one but the others not so much) The city of Celina was ordered by the Ohio EPA in 2003 to resolve its MCL (maximum contaminant level) violations of its drinking water. The Celina water ...

**Physics**

Find the frequency of a wave whose period is 0.320s.

**Chemistry**

I am having trouble answering this. please help! Q: Cereol is a newly discovered compound in corn flakes. A biologist suspects that it increases mental ability. She is making a solution to test on rats. First she makes a stock solution. She discovers that this is too ...

**spelling**

I need to call my lawyer

**Math**

The answer is C

**Square roots**

No its isn't that I found how you do it that would part of it.

**Square roots**

The diagonal of a square has length square root 2 X s, where s is the length of a side of the square. What is the length of the diagonal in a square with sides that are 13 cm? Round your answer to the nearest tenth.

**Physics3**

The answer is 2. Fnet=Sqrt of 2 F

**science**

A 68.4g sample of Potassium Chloride was added to 200g of water at 20 degrees celsius. Is the solution saturated, unsaturated, or supersaturated?

**Chemistry**

A scientist wants to make a solution of tribasic sodium phosphate, , for a laboratory experiment. How many grams of will be needed to produce 625 of a solution that has a concentration of ions of 0.800

**AgBio1**

Evidence shows that hippos and whales are closely related organisms. How might evolution and adaptation account for similarities and differences between them.?

**Pre-Calc**

How would I solve: X^(4/3)+X^(2/3)=28