L.Bianchessi

Im a freshman in college and I just took Chem1, Trig, and Drama (12units). I am planning on taking Chem2, Pre-Calc, and Art1 for spring sem. (13units). I'm not sure if this is too much to take for next semester considering two five unit classes or should...

13 years ago

measurements of carbon 14 taken from linen wrappings of the book of isaiah from the dead sea scrolls indicate that the scrolls contain 79.5% of the carbon 14 expected in living tissue. how old are these scrolls if the half life of carbon 14 is 5730 years?...

13 years ago

The activity of carbon 14 in living tissue is 15.3 disintegrations per minute per gram of carbon. The limit for reliable determination of age is based on carbon 14 is .10 disintegration per min per gram of carbon. Calculate the max age of a sample that ca...

13 years ago

Find the slope. (3,1/3) and (3+h, 1/(3+h)) I think I get -1/ 3(3+h) ???

13 years ago

A chemist trying to synthesize a particular compound attempts two different synthesis reactions. The equilibrium constants for the two reactions are 23.3 and 2.2 X 10^4 at room temp. However, after 15minutes the chemist finds that the reaction with the sm...

13 years ago

Ranking equilibrium constants from largest to smallest according to an image?Ethene (C2H4) can be halogenated by the following reaction: C2H4 (g) + X2 (g) -><- C2H4X2 (g) where X2 can be Cl2 (green), Br2 (brown), or I2 (purple). Examine the three figures...

13 years ago

This is probably easier then my making it but... Calculate the ph of a forming acid solution that contains 1.35% forming acid by mass. Assume a density of 1.01g/ml for the solution.

13 years ago

How many significant figures are in 0.0? And how about 0.00?

13 years ago

The value of Kw increases with increasing temperature. Is the autoionization of water endothermic or exothermic? In thinking its both but I don't know how to explain it.hmm...

13 years ago

Find the pH of mixture of acids. 0.185 M in HCHO2 and 0.225 M in HC2H3O2 Im using an ice chart of weak acid and putting in strong acid in H+ initiAL concentration. I've done the problems many different ways but cannot seem to get the right answer help ple...

13 years ago

Find the pH of each mixture of acids. 0.115 M HBr and O.125 M HCHO2. I TRIED DOING THIS PROBLEM THE SAME WAY AS THE ONE BEFORE BUT IT DIDN'T WORK. THE PH SHOULD BE 0.939. I did HBr as stronger acid and got concentration of H+ and put it into the ka expres...

13 years ago

Find the pH of each mixture of acids. 0.020 M HBr and 0.015 M HClO4. They are both strong acids Si they dissociate completely. Si do I just add 0.020 and 0.015 and take the -log of that concentration to get the pH? Like thus.... 0.020+0.015=0.035 pH=-log(...

13 years ago

Determine whether each cation is acidic or pH neutral. For those cations that are acidic, write an equation that shows how the cation acts as an acid. A) Sr+2 B) Mn+3 C) C5H5NH+ D) Li+

13 years ago

Let f(x)=3x-4x^2 Find f o f o f So... F(f(x)) I got a really big answer..... I think I might have done something wrong when doing the distributing algebraic work.

13 years ago

Write two reactions for NaHCO3, reacting with water in one NaHCO3 is acting as acid the other as a base. Is 0.10M solution going to be acidic or basic? Explain. I write the two rxns but what do I do with then...

13 years ago

A 0.035 M solution of a weak base has a pH of 10.88. What is the Kb for the acid? Where Di I even begun**???

13 years ago

Let P(x,y) be a point on the curve y=16-x^2 and let A be the point directly below P on the x axis. If O is the origin, find the area and the perimeter of triangle OAP as functions of x. I got Area=x(8-1/2x^2). Is that right? And perimeter= x+16-x^2+ (squa...

13 years ago

find the point on the line y=2x-1 which is closest to the point (2,-1). I used distAnce formula and got D= (square root 5x^2 -4x +4) I did.... D=square root (2-x)^2 + (-1-(2x-1))^2 What do I do now?

13 years ago

A town has a population which is growing linearly. In 1970 its population was 36,000 while in 1985 its population was 63,000. Find a formula for its population P(t), where t=0 corresponds to the year 1970.

13 years ago

Find the maximum value, and where it occurs for eAch function. G(x)= (square root -x^2+4x+12)

13 years ago

Find the domain of f(x) = 1/ (square root 2x^2-7x-15) I tried setting 2x^2-7x-15 greater or equal to zero but I don't know where to go from there to solve for my domain. Help please!:)

13 years ago

Calculate the percent ionizationof a 0.15 M benzoic acid solution in pure water Nd also in a solution containing 0.10M sodium benzoate. Why does the percent ionization differ significantly in the two solutions?

13 years ago

One liter of arterial blood at sea level contains approximately 3 mL of dissolved oxygen and 197 mL of oxygen bound to hemoglobin. If a normal individual has a cardiac output at rest of 5 liters per minute, how much oxygen is carried to the tissues per mi...

13 years ago

A classmate who has been standing still for several hours working on a laboratory experiment suddenly faints. Based on what was studied in this unit, what is the probable explanation?

13 years ago

Two

13 years ago

When adding or subtracting the sum is to the least number of decimal places When multiplying or dividing the sum is least number of Sig figs.

13 years ago

You use the point slope equation. I believe it is.... y-y1=m(x-x1)

13 years ago

Solve for y. y-(-5)=-3(x-(-2)) So y+5=-3x-6 Y=-3x-11 Basically you are now in Y=mx+b form

13 years ago

Oh, okay. Do I always use that equation for any order rxn involving time? How about the units, would it be yrs^-1 or just years?

13 years ago

How do you know what number goes on the top and bottom for the disintegration?

13 years ago

I got that same interval notation. Except I subtracted the 4/x^3 to the other side and ended up with (x+2)(x-2)/x^3 less than or equal to 0. Then I drew one of those. Line grAphs Nd put circles at -2,2, and an undefined at 0. Then figured out where the x'...

13 years ago

15 I believe

13 years ago

8less than or equal to x less than or equal to 15

13 years ago

I'm thinking c,b,a?

13 years ago

Usually the salt is contained in what they refer to as a salt bridge. Connecting the electrodes of the experimented ions.

13 years ago

Delta T= (95Joules) / [ (16g Au) X (0.128 J/g C)] Change of temp= 46Degree celcius

13 years ago

I think I made a mistake.... 1.35g/100g solution=0.0135grams 0.0135g/1.01g=0.01337ml Then... 1.35g/46.03g CH2O2= 0.0293mols Then... 0.0293mol/ 1.337X10^-5 = 2.19X10^3 M pH= -log[H+] PH=-log(2.19X10^3) But I get a negative ph.

13 years ago

Each person can stand 4 different ways I believe So I'm thinking 16 different ways all together.

13 years ago

use permutations and combinations on these types of problems.

13 years ago

I did this same experiment a couple weeks ago. We are measuring the amount of time it takes for the thiosulfate to run out. So to calculate the concentration of the thiosulfate ion. You can multiply the milliliters of thiosulfate in whatever trail you are...

13 years ago

Yes, exactly! Since we are diluting we can use M1V1=M2V2. So Concentration of thiosulfate X Amt.(volume) of added thiosulfate = (75ml)total volume X the Concentration of the new concentration of thiosulfate in the flask(what you are trying to find) The th...

13 years ago

Solve for y for the given equations. Putting it in y=mx+b form. Then do the negative reciprocal of the slope from the given equation. After that use the point slope formula to calculate the new equation using the given point and your new slope. Do you get...

13 years ago

I just wrote mine in terms of the concentration of the thiosulfate. Pretty much I isolated the variable I was trying to find. :) same thing though!

13 years ago

Oh, you just divide the negative to each side and get y=5x-2. Then use y-y1=m(x-x1) y-(-2)=-1/5(x-10) Then solve.

13 years ago

Oh and the answer would be y=-1/5x

13 years ago

Well I haven't done trig in a long time but u believe... You divide the 2 to each side to get Cos(3x-72)=1/2 Then do the inverse to both sides to get rid of the cos and end with 3x-72=60 degrees So x= 44 degrees Cosine is positive in quad1&4 So 44degrees...

13 years ago

44&124degrees

13 years ago

It you cannot determine the concentration of the mixture by forming a double replacement became you form products that are the same as the reacting because you are mixing two acids.

13 years ago

I plugged in 3x-72=___ (set them equal to 420,660,780,1020) Answer:44,124,164,244,284 degrees

13 years ago

Oh, okay so increasing the kw makes the reaction produce more OH- and H+ so energy must be increasing on the reacting side to produce a endothermic reaction meaning energy is being absorbed to obtain a high temperature for the kw. Ahh...I get it! Thank yo...

13 years ago

I got concentration of HCOOH rxn to be 5.77X10^-3. And the CH3COOH rxn to have concentration of 2.01X10^-3. I added those together to get 7.78X10-3. What do you mean add to ka expression? I keep getting 1.35 now.

13 years ago

Yes.

13 years ago

Determine your moles of HCl. Then use your equation to convert moles of HCl to moles of Ca(OH)2 then to grams of the calcium hydroxide. The ratio would be 2Mol HCL to 1mol of Ca(OH)2

13 years ago

So you get 0.01304 mol HCL. YOU GET 0.483GRAMS OF CALCIUM HYDROXIDE.

13 years ago

WELL FOR SIN AND AND CSC YOU KNOW THAT THE INTERVAL HAS TO BE BETWEEN 0<X<2PI SO YOU CAN FOR (B) 0<X-PI/2< 2PI AND THEN SOLVE FOR X. TO SEE WHERE THE GRAPH WILL LIE BETWEEN YOU GET PI/2<X<5PI/2 FOR TAN AND COT YOU KNOW INTERVAL IS PI/2<X<PI/2. FOR COS AND...

13 years ago

YOU COULD SEE THE GRAPH BY GOING TO GOOGLE AND ENTERING IN WOLFRAM ALPHA A WEBSITE AND ENTER IN THE EQUATION. THEY USUALLY WILL GRAPH IT FOR YOU BUT YOU NEED TO DETERMINE THE PERIOD, AND ETC. STUFF FOR YOUR GRAPH.

13 years ago

you would do a conversion factor. 50g of H2SO4 x 1mol sulfuric acid/ molar mass of sulfuric acid x grams of H2/ 1mol H2 You get grams of H2. Get it?

13 years ago

Oh okay yeah I didn't add the 5.77x10^-3 to the weaker acid. So I determine concentration of stronger acid then put that H concentration into the weaker acid then I determine the concentration of the H of CH3COOH and get 7.02x10^-4 and add the H+ concentr...

13 years ago

Na+4 doesn't exist because sodium can only give away one electron because that's all it has. But maybe you are trying to say... Na3PO4---> 3Na^+ + PO4^-3

13 years ago

You would need the chemical formula for plant food to see what it produces as products.

13 years ago

You would add H2O to the acid and determine the products from a double reaction. The acid who gives the H+ up is the acid and the one who accepts it is the base. You look over at the products and those are called the conjugates. Do for example... 1) HSO4-...

13 years ago

The acid on the left has a conjugate base on the right. H20 is acting as base, and H3O+ conjugate acid. It's pretty much the opposite.

13 years ago

Do you mean ax^2+ bx+c=0 ??

13 years ago

Well we can graph the points and form a triangle. We can then find the distance between each point(side). And if two sides have the same distance we know that the triangle is isosceles. Distance between AC: D=square root of (5-0)^2 +(2-1)^2 D=radical 26 d...

13 years ago

Well you subtract the 16 to get your equation equal to one. Do x^2/16 + y^2/4=1 Your center is 0,0 Your eclipse would be horizontal. Do when graphing put a point at (0,0) then go 4 spaces in the negative and positive direction on the x-axis. Then go up 2...

13 years ago

The cost equity. Because... Cost debt+ cost equity= WACC

13 years ago

Well... You know that KOH is a strong base... So it ionizes completely. KOH----> K+ +OH- So you need the molarity of KOH... So.. 1.100g/.5500 L x 1mol/56.11g KOH = 0.0356 M KOH So since KOH is strong... Concentration KOH, K+, and OH- = 0.0356M pOH=-log(0....

13 years ago

Cos inverse of 1/4 =2t So do cos inverse of 1/4=75.52... So... 75.52...= 2t Solve for t. T=37.76..

13 years ago

Is the 5 an exponent?

13 years ago

Well if your cheap calculator has a exponent. You could do 2.72^-4.7 You get 0.0090683057 It's pretty close!

13 years ago

Well you use the area of a square formula. Do. You do (3x+2)^2=Area Get it?

13 years ago

No it would not. You convert 536.8 g to ml by using the density. You get 753 so no you cannot fit it into a 750 ml flask.

13 years ago

Is it set equal to anything?

13 years ago

Answer: (square root 1-25x^2 )/ 5x

13 years ago

That's true but you should include how the temperature affected the rate and which way the equilibrium shifted and how the color change tells you which way it shifted. When you heat the test tube the solution turned a dark purple/blue color. And when you...

13 years ago

The ice bath one would take longer because it takes more energy for the solution in the flask to form products thus, the activation energy is higher making the reactants need energy so it is endothermic.

13 years ago

Example--Difference of squares: (x^2 + 5x-6) = (x+6)(x-1) 1. Write an x in both parenthesis 2. Find factors of 6. (6x1 or 3x2) 3. The inner (6x) plus the outer (-1x) should equal the middle term 5x Or you could foil. Trinomial: (a+b)(a^2-ab+b^2) (a-b)(a^2...

13 years ago

285 miles to travel between two cities

13 years ago

2cm.... 2cm x 4cm x3cm=24cm^3

13 years ago

Well 1min =60 sec ... So 60 sec +25 sec= 85sec

13 years ago

Well since sulfuric acid is a strong acid it dissociate completely so you just do the -log(0.10) =pH

13 years ago

Volume =length x width x height You just multiply all three numbers to get what ever number m^3.

13 years ago

Cr+3, Na+, I2, F2 Oxidized- lose electrons

13 years ago

You could probably set up a proportion. so.... 0.160/x= 0.205/1.5ppm Solve for x.

13 years ago

S=5

13 years ago

160Angstrom

13 years ago

Average rate of disappearance just means slope! So... (0.535-0.268)M / 0-520sec =5.13 X 10^-4Ms^-1 Tada!

13 years ago

figured it out. but need help on my other question please!:)

13 years ago

oh, okay that makes sense its like a conversion factor. Thank you!

13 years ago