# Posts by dan

Total # Posts: 1,211

**Chemistry**

Aqueous sodium sulfide reacts with aqueous calcium chloride to make a solid. The % yield is 85%. Calculate the amount of each reactant needed to actually make 3.0g of the solid.

**Chemistry**

We did a titration of calcium hydroxide lab in chemistry, once with and once with edta, we have to calculate the solubility for both, and the ksp, for the hcl I did (concentration)*(Volume of hcl used) then that answer divided by two divided by the amount of divided by the ...

**Physics**

Someone please help. A radio needs to be tuned to a range of values between 526.5 - 1606.5 kHz. Choose a combination of inductor and variable capacitor values within a tuned circuit that would meet this requirement. Choose practical components from standard vendor web sites (e...

**math**

Construct a 2 × 2 matrix that defines a shear of factor 4 in the y-direction, followed by a scaling of factor 5 in the x-direction, followed by a reflection about the y-axis.

**Math**

Find a single matrix that defines a rotation of the plane through an angle of π/6 about the origin, while at the same time moves points to five times their original distance from the origin.

**Linear Algebra**

Yeah I understand that part, but what about projection onto vector u?

**Math**

Did you manage to figure out this assignment? I have the same portfolio assignment and it is super confusing!

**Writing**

Where is somewhere I can get a definition from that I can cite as a scholarly source? My prof said that we can't use an online dictionary.I need to find the definition of universal health care if that matters

**Chemistry**

I did a lab, an kinetics lab (iodide clock) and in my lab report I have to calculate the initial rate in mol L-1 s-1 and I'm not sure how to do that. I have the [I-] and [S2O82-] in mol L-1 already. The reagents are [KI] [NaCl] [Na2S2O3] [Na2SO4] [K2S2O8].

**U.S History**

Are advertisements valuable primary sources/reflections of culture? Why or why not?

**Chemistry**

27% of heat produced by the stove's gas burner is transferred to the soup in the covered pot, the rest is lost. Determine the total mass in grams of methane that must be burned to heat 800 ml of water from 22 to 90 degrees C. The density is 1.08 g/ml and the specific heat ...

**Chemistry**

I have to write the rate law for two elementary reaction equations A ) 2a+b>c+d B ) X+Y>Z I'm pretty sure it's just k[ A ][ B ] and k[ X ][ Y ] but does the coefficient affect it in this case? is it [ A ]^2 ?

**Chemistry**

PART 1 >>Trial 1 Reactant Solution A 10 ml I^-, 5.0 ml S2O3^2- Reactant Solution B 10 ml S2O8^2-, 1 ml starch time to react = 10 seconds >>Trial 2 Reactant Solution A 10 ml I^-, 5.0 ml S2O3^2- Reactant Solution B 5 ml S2O8^2-, 1 ml starch time to react = 20 seconds...

**Chemistry**

I looked part 2 for a bit and by looking at the slow step and using that to figure out the rate law I think it might be mechanism 2, would this be right?

**Chemistry**

PART 1 >>Trial 1 Reactant Solution A 10 ml I^-, 5.0 ml S2O3^2- Reactant Solution B 10 ml S2O8^2-, 1 ml starch time to react = 10 seconds >>Trial 2 Reactant Solution A 10 ml I^-, 5.0 ml S2O3^2- Reactant Solution B 5 ml S2O8^2-, 1 ml starch time to react = 20 seconds...

**Chemistry**

I have to write the rate law for two elementary reaction equations A ) 2a+b>c+d B ) X+Y>Z I'm pretty sure it's just k[ A ][ B ] and k[ X ][ Y ] but does the coefficient affect it in this case? is it [ A ]^2 ?

**Math**

I need to find the limit as x goes to 3 of (1-sqrt(x-2))/(x-3)), I know the answer is -1/2 but I have no idea how to get to the answer, and help would be appreciated

**Chemistry**

I have to calculate the heat capacity of a coffee cup calorimeter, but I'm not sure how. I have NaCl and NaOH, they both start at the same temperature, and I have the mass of the solutions used. I'd appreciate the help!

**Science**

Hydrogen peroxide can be prepared in several ways. One method is the reaction between hydrogen and oxygen, another method is the reaction between water and oxygen. Calculate the ΔG°rxn of each reaction below? 1) H2(g) + O2(g) <==> H2O2(l) ΔG°rxn=? (in ...

**Math**

find the limit as x->3 of (1-sqrt(x-2))/(x-3) I'm not sure how to get the answer, I know it's -1/2, but I don'y know how to get that.

**math**

The graph of y=x^2 is transformed by a stretch of scale factor 2 parallel to the x axis, followed by a translation of (0 3). WRITE DOWN the equation of the new graph

**chemistry**

12

**chemistry**

16

**Math**

Emily wants to make a regtangular model with a height of one connecting cube. she wants to make the model in exactly 2 different ways. how many connecting cubes could Emily use to make the model in only 2 ways. A6, B12, C16, D18

**Chemistry**

A chemical technician prepares Ni(NH3)6Cl2 by adding 4.55 g of solid NiCl2·6H2O to 25 mL of 6.0 M aqueous NH3. What is the maximum mass of Ni(NH3)6Cl2 that will be produced? how would I do this question?

**Chemistry**

I have to list distributed benzene in order of polarity, and I don't think i know how to do that, but does polarity have to do with dipole moments?

**Chemistry**

I just need someone to check over my answers, I'm pretty confident in all of them! In which six-membered hydrocarbon rings are all of the C-C-C angles roughly the same, i.e., within 1o? Select ALL that apply. Question 1 options: A)cyclohexane B)cyclohexene C)1,3-...

**Chemistry**

I've changed my answer for part one to a) N-O bond length in >>> 4 b) N-O double bond in NO2H >>> 1 c) N-O bond length in NO3- >>> 2 d) N-O bond length in NO2- >>> 3 e) N-O single bond in NO2H >>> 5

**Chemistry**

Draw the best Lewis structures for NO+, NO2-, NO2H, and NO3-. Based on the Lewis structures, list all of the the N-O bonds lengths in order of shortest (1) to longest (5). N-O bond length in >>> 2 N-O double bond in NO2H >>> 1 N-O bond length in NO3- >>...

**Math**

smash?

**Chemistry**

NEVER MIND. it was hydrogen bonding, I didn't see the OH group

**Chemistry**

Identify the predominant intermolecular force in each of these substances. 1. Hydrogen 2. Dipole-Dipole 3. London A)H20 B)NH3 C)CH3 C=O OCH3 D)CH4 E)CH OH-C-OH CH3 what I have so far is A) 1 B) 1 C) 2 D) 3 E) I'm not sure about E, I think it might be dispersion?

**English**

Do your own work.

**Critical thinking (Check)**

4. The newly elected Canadian government is planning on withdrawing Canada’s CF-18 jets from the allied bombing campaign against the Islamic State (aka ISIS, aka ISIL, aka Daesh) forces within Iraq and Syria. The Conservative opposition in Parliament is opposed to the ...

**Critical thinking**

what I was thinking was that the premises are good and the argument is good the conclusion is flawed because those mean it's a good class, but not necessarily the MOST important class

**Critical thinking**

the conductive argument is talking about critical thinking classes the premises are all separate premises leading to the conclusion P1. Critical thinking teaches the fundamentals of good reasoning. P2. Critical thinking helps people learn how to detect bad reasoning in the ...

**Critical thinking**

3. Consider the following conductive argument: P1. Critical thinking teaches the fundamentals of good reasoning. P2. Critical thinking helps people learn how to detect bad reasoning in the arguments they hear and read. P3. Critical thinking principles underlie all the academic...

**Critical thinking**

((Remember that for an inductive inference with linked premises to be valid the premises must be acceptable and they must be sufficient to render the conclusion probable. An assessment of inductive validity requires you to explain your reasons for weighing the evidence as you ...

**Critical thinking**

I have finished my assignment I just need someone to read it over and check my logic, please and thank you! 1. Read the following argument and answer the question that follows: 1. According to the 2010/11 Statistics Canada census aboriginal Canadians constituted 4.3% of the ...

**Philosophy**

If you have a inductive argument, and you're evaluating if the conclusion is valid or not, if you can figure out a different conclusion is it valid or not?

**math**

Can you tell me what, (in greatest to least) the order is... 1/2, 4/5, 5/6, 2/3 7/8, and 1/4. this will be greatly appreciated.Thx.

**calculus**

gay

**math**

the spanish club is selling t-shirts and baseball caps as a fund raiser if the baseball cap cost $1.13 to make and sell the shirt for $5 how much profit does the club make for each shirt?

**PHYSICS**

A Solid Cube Of Steel Has Each Side 10cn Long.Find Its Mass If The Density Of Steel Is 6.5g/cm

**physics**

E.P=mgh M=0.5 G=10ms-2 H=1.8-1.3=0.5 E.P=0.5*10*0.5 E.p=2.5

**Chemistry**

1. In the lab you will be provided with 0.1 M sodium hydroxide that you will standardize using KHP. What is implied by writing the NaOH concentration as 0.1 M? a) After performing your standardization and calculations, any deviation from 0.1000 M is due to experimental error. ...

**Chemistry**

1. Which molecule should have the higher dipole moment, and why? a) COF2 because it contains more F atoms. b) COFH because the polar bonds in COF2 nearly cancel each other out. c)COF2 because it contains more lone pairs. >> I think the answer is a)?

**Chemistry**

Anthracene is a yellow, crystalline solid found in coal tar. Complete this structure for anthracene, C14H10, by adding bonds and hydrogen atoms as necessary. What type of hybrid orbitals are utilized by carbon in anthracene? >>sp3 How many σ bonds and π bonds ...

**Critical thinking**

I've seen these questions asked today/yesterday (and answered) but I just wanted someone to check over my answers to see if they make sense. 1. Assume that the conclusion of an argument is the claim: It is wrong to inflict suffering on animals. For each of the following ...

**Philosophy**

I've seen these questions asked today/yesterday (and answered) but I just wanted someone to check over my answers to see if they make sense. 1. Assume that the conclusion of an argument is the claim: It is wrong to inflict suffering on animals. For each of the following ...

**math**

21 boys, 21 girls. 7:5 - 6 girsl is 21 boys to 15 girls [think -6]

**chem**

What is the electron configuration for the aluminum ion? Phosphide ion? Do NOT use shorthand notation! My answer but when I input it I get it wrong why? Al: 1s^2,2s^2,2p^6,3s^2,3p^1 P: 1s^2,2s^2,2p^6,3s^2,3p^3

**Chem**

In the reaction that forms aluminum nitride from its elements, which element is being oxidized?

**Newburgh**

Algebra

**CHEMISTRY - BATTERIES**

What is the voltage and the Gibbs Free Energy for the following reaction? (Assume standard conditions) 3Sn^2+ (aq) + 2Al (s) --> 2 Al^3+ (aq) + 3 Sn (s) Now calculate the Gibbs Free Energy for the above reaction if Sn^2+ (aq) is 0.15 and Al^3+ (aq) is 1.8

**Chemistry**

You synthesized copper (I) chloride and copper (I) oxide. How do they differ from their copper (II) analogs? comment on the stability of these moist solids in air. If unstable, what is the likely product of decomposition? -I'm not really sure where to go with this one, ...

**Math**

** -4(-5)+1=??

**Math**

It's not b for example, for -5, put that in where it says x in the original equation so, 4*(-5)+1=??

**Math**

the way to solve this question is to plug in the values to the "x" in the equation

**Math**

What did you get when you tried to answer this?

**Chemistry**

How do I calculate the percent yeild of copper give the mass and concentration of Cu(NO3)2 and the final mass of copper

**Chemistry**

is it easy to distinguish between between the different oxidation states of copper? why? -I answered yes because copper (I) is not as stable as copper (II), and there is a noticeable colour difference You synthesized copper (I) chloride and copper (I) oxide. How do they differ...

**Chemistry**

In a copper cycle lab if I add HCl to CuO to produce CuCl, what would a word equation for that reaction be? Is it a chemical reaction? and also for that step what complexes are observed? what does that mean?

**Chemistry**

1. is it easy to distinguish between between the different oxidation states of copper? why? 2. You synthesized copper (I) chloride and copper (I) oxide. How do they differ from their copper (II) analogs? comment on the stability of these moist solids in air. If unstable, what ...

**Chemistry**

In a copper cycle lab if I add HCl to CuO to produce CuCl, what would a word equation for that reaction be? Is it a chemical reaction? and also for that step what complexes are observed? what does that mean?

**Critical thinking**

I posted this question earlier but I still need help with this. I need to explain how this argument could be constructed as circular, the argument is [W]e may observe, that there is no species of reasoning more common, more useful, and even necessary to human life, than that ...

**Critical thinking**

I went over the argument and separated it into different parts, and from that I got 1)There is no reasoning more useful/common that testimony 2)Some say testimony is not be founded on the relation of cause and effect 3)It’s good enough to notice that out promise in this ...

**Critical thinking**

I need to explain how this argument could be constructed as circular, the argument is [W]e may observe, that there is no species of reasoning more common, more useful, and even necessary to human life, than that which is derived from the testimony of men, and the reports of ...

**Philosophy- Critical thinking**

U of M? (I've asked the first pat recently) it's a few down, go look at it

**Critical thinking - Reed?**

That is what I meant, thank you for correcting me.

**Critical thinking - Reed?**

You're right, so it should be unacceptable by observation. Good spot!

**Critical thinking - Reed?**

It could also be by testimony, but it is something someone would know by paying attention to news or other stuff like that..

**Critical thinking - Reed?**

Thank you for your help!

**Critical thinking - Reed?**

vi) + xi) Since I myself have not been to Japan and have to rely on looking it up else where wouldn't it be testimony? vii) Could it be acceptable by observation since that it something we have seen ourselves?

**Critical thinking - Reed?**

I have finished my assignment I and would like if someone could look it over and tell me if I'm really off on any points? (i) John will either score 10/10 on the assignment or he will not -Acceptable by observation (ii) David Johnston is Canada’s head of state -...

**Critical thinking**

I need to identify if each premise is acceptable or unacceptable, and for this the conditions of acceptability are acceptable by observation, testimony, authoritative testimony (only use if the premise explicitly refers to an authority), and a priori And the conditions of ...

**Critical thinking**

I need to identify if each premise is acceptable or unacceptable, and for this the conditions of acceptability are acceptable by observation, testimony, authoritative testimony (only use if the premise explicitly refers to an authority), and a priori And the conditions of ...

**Chemistry**

A 18.7 g sample of CaCO3 was treated with aqueous H2SO4 producing calcium sulfate, water and 3.65 g of CO2(g) according to: CaCO3(s) + H2SO4(aq) -> CaSO4(s) + H2O + CO2(g). What was the percent yield of CO2?

**physics**

A sphere of mass 78 kg is attached to one end of a rope as shown in the figure below. It is found that the rope does an amount of work W = 3550 J in pulling the sphere upward through a distance 4.6 m. Find the work done by the force of gravity on the sphere. My work W= -78 * 9...

**Chemistry**

What is the concentration of Fe(III) with a stock concentration of .00025 M in a solution of 1 ml FeCl3 and 9 ml of HCl? 2 ml of FeCl3 and 8 ml of HCl? 3 ml of FeCl3 and 7 ml of HCl? 4 ml of FeCl3 and 6 ml of HCl? 5 ml of FeCl3 and 5 ml of HCl? I got .000025 .00005 .000075 ....

**Chem**

Complete combustion of 8.30 g of a hydrocarbon produced 26.7 g of CO2 and 9.10 g of H2O. What is the empirical formula for the hydrocarbon? My Work: First I tried to find the Amount of C and H in the product... Which I got 1 Mole of Carbon and 2 moles of Hydrogen... Now I'...

**Science**

I have a question from an old exam that I need help to understand, i'm not sure where to start An electron in an electronically excited hydrogen atom undergoes a transition from a 6d to a 2p orbital, resulting in the emission of a photon. The photon strikes a metal surface...

**Science**

I have a metal sheet of indium, and when a uv light with a wavelength of 265 nm is shone on it the surface ejects electrons that have a kinetic energy of 8.31x10^-20 J per ejected electron. I'm asked to find the threshold frequency, I need to know how to find it.

**5th Grade**

the decimal place right after the decimal is the tenths, the next is the hundredth, then thousandths, then ten thousandths, ect, in that pattern, so what is the hundred thousandths place?

**Language arts**

The author of a book is the person who wrote the book, so what is the comparison to the suite.

**physics**

bob is pushing straight down on the box, which is in the direction that the force of gravity is, so the force downwards is equal to 12+mg. Since there is no acceleration in the up/down direction, Fn=Fapplied=Fg

**physics**

W=mg is the equation for weight, so rearrange this equation to find mass, which ends up being W/g=m. 597 N/9.8 m/s^2=?

**algebra**

A particular style of sunglasses costs the retailer $80 per pair. At what price should the retailer mark them so he can sell them at a 20% discount off the selling price and still make 30% profit on his cost?

**Math**

Thank you so much!

**Math**

I realize i need to do "complete the square" and here is what i got... (4/4)x^2-(12/4)x+(61/4)=0 x^2-3x+15.25=0 x^2-3x=-15.25 x^2-3x+2.25= -15.25+2.25 (x-1.5)^2=-13 x=1.5 +/- sqrt(-13) I know i am wrong... help?

**Math**

solve for x (4/4)x^2-(12/4)x+(61/4)=0

**Algebra**

If z = (x-8)/(2x) then x=?

**chemistry**

Name and draw the molecular structure of this compound CH3CH(C2H5)CH(CH3)CH(C3H7)CH2CH3

**7th Grade Science Help**

what about 23 please lun

**Math**

Which of these numbers is the smallest? 0.24, 0.02, 0.11, 2, 0 (Is 0 considered to be the smallest number here?)

**Chemistry**

12

**algebra**

A boy can row 18km. downstream and return a distance of 16 km. upstream in 5hrs. If the rate of the current is 6km/hr, What is the boy's rate of rowing in still water?

**algebra**

A boy can row 18km. downstream and return a distance of 16 km/hr upstream in 5hrs. If the rate of the current is 6km/hr, What is the boy's rate of rowing in still water?

**chemistry**

If a rectangular solid has a mass of 59.345 g and measures 10.05 cm by 5.20 cm by 1.25 cm, what is the density of the solid?

**Math**

In a 4 mile walk, Jenny covered the first 2 mile in 40 minutes. How fast should she walk the rest of the way to average 3.5 miles per hour overall?