Ninjakat

Thank you I was able to find the activity series but what doesnt make sense is both of them dont really work 100%

With silver mixing with nickle because its closer together on the activty series, one chart states (no change) although the other one does.

There should be a reaction, ALTHOUGH it also states on the second chart silver reacts slightly with zinc, but they are polar opposites on the activity series... doesnt that mean they arent supposed to react?

How do u create an activity series?

Bah... I honestly dont get this. Its electro chem

Question: Consider the following lab data, gathered from two different students

Student 1: Lab data for the determination of an activity series of metals

Chemical | Ag+(aq) | Ni+2 (aq) | Pb+2(aq) | Zn+2 (aq)

--------------------------------------------------------------

Ag(s) |//////////////| No change | No change | No change

--------------------------------------------------------------

Ni(s) | Grey coating| /////////////| Black coating| No change

forms on nickle forms on nickle

--------------------------------------------------------------

Pb(s) | Grey coating| No change |//////////////| No change

forms of lead

--------------------------------------------------------------

Zn(s) |Grey coating | grey coating | Black coating |///////////

in forms of zinc|in forms of zinc| in forms of zinc

Student 2: Lab data for the determination of an activity series of metals

Chemical | Ag+(aq) | Ni+2 (aq) | Pb+2(aq) | Zn+2 (aq)

--------------------------------------------------------------------------------------------------

Ag(s) |//////////////| Grey coating on silver | black coating on silver | grey coating on silver

--------------------------------------------------------------------------------------------------

Ni(s) | Grey coating| /////////////////////////| No change | No change

forms on nickle

---------------------------------------------------------------------------------------------------

Pb(s) | Grey coating| Grey on coating lead |////////////////////////////| No change

forms of lead

---------------------------------------------------------------------------------------------------

Zn(s) |No change | No change | No change | //////////////

a) Which student has valid results? (Hint: use the data to create an activity series.) Justify your answer by stating the errors in the incorrect observation table.

B) Suggest two reasons why a student may experience poor results during this type of chemical experiment.

IMO, I think its just because subconsciously we remember these vivid dreams and they only reoccur because its just a memory. I wouldn't know if there is a scientific explanation behind it though.

No I dont know any of that. This is just college level grade 12 chem and they didnt cover anything else. Other then how to draw hydrocarbons and what is in them.

So please I really need help with this I dont want complex answers this is college level. I dont understand when you guys talk all "university" level.. like I need someone to BREAK it down into simple language and tell me what To do for this. I don't know much at all.

I did a lab for destillation online but it was with crude oil.

3 hydrocarbons im unsure how I'd do the same lab with more then one material?

Well at different boiling points makes it evaporate.

So for 3 hydrocarbons would you do 3 different experiments?

Each one recording the vapour at different boiling points?

The problem with online learning is they give you nothing to work with except questions. I did absolutely nothing on this topic so some help would be nice.

Design a laboratory set-up that would enable you to separate a mixture of three hydrocarbons with different boiling points. Explain the reasons for the apparatus you would need in your set-up, and develop the procedure you will use to separate the hydrocarbons. You should also include a blank data table for recording results. (Note: You are not going to perform the actual experiment, so do no report any results)

Hey guys, someome on the chat portion of the website was able to help me last night , but thanks for your time

25. h20 = 17.99 g/mol

nh2o = m/M

= 12.2g / 17.99 g/mol

=0.67 moles

Since 1 H2O = 1 H2 = 1:1 ratio

H = 0.67 moles

26.

2 CH + 3 O2 --> 2CO+4H2O

nCH4 = 45.6g / 16.01 g/mol = 2.85

nO2 = 73.2g/31.98 g/mol = 2.28

3:2 Ratio, Oxygen is the limited reactant.

Since CO is equal to 28 g/mol

2.28 / 3 moles of oxygen x 2 moles = 1.52 moles

1.52 x 28 = 42.56 moles.

So you may begin with calculating number of mole of substances produced per reaction, and calculate how many reactions have been performed.

What question are you talking about? And what am I using? like.. i said no blunt comments be specific.

Im unsure what im supposed to do. Please dont just be blunt im actually lost here.. I need direction.

25. The following reaction represents the decompostion of water:

2 H2O ---> 2H2 + O2

How many molecules of hydrogen are produced from the decompostion of 12.2 g of water into its elements? (4 marks)

26. Determine the mass of carbon monoxide that is produced when 45.6 g of methane, CH4, react with 73.2g of oxygen gas, O2. The products are carbon monoxide, CO, and water vapour H2O. (7 marks)

I just watched a documentary on the pet food industry today and these are the facts that where stated. Seems all our pet foods no name brand all the way to high end brands are ALL produced at ONE company in Toronto which controls all of north America. All these dry dog and cat foods contain grains that where shipped from China (which have been found in the past to contain plastic ) which can be harmful to your dog and are often the source of poison and recalling in the pet food industry. It's also said that even though "Chicken" may be the first ingredient on the dog food label there is x3 the amount of GRAIN. Your pets should consuming more meat then grain products. On the sad note there is very little to none nutrition training in veterinarians. There is no difference from our compliments brand to Purina or IAMS pet foods.

Cats also are complete carnivore and the fact that there is found a lot more grain products involved then meat suggests that there may be an increase if complications within your cat in a duration of time. Cats usually have problems digesting grain products. It is kinda scary knowing most things you could possibly feed your pet could complicate things or even make your pet sick, and the fact most Veterinarians have very little to no pet food training you shouldn't trust their suggestions. Although working in an animal hospital myself I tend to find they feed their pets brands such as Science Diet or Nutrience.

I dont get it.. i get 18.6

Doesnt P+q = 1..

I dont understand what the hell im doing.

If I square 18.6 I get 4.31 which is still wrong

Although not absolutely sticking to the question I find it interesting to comment the following related theme.

Very occasionally a chick from a non-fertilized egg is born to a female virgin bird (or at least I have heard so). This is called I belive parthenogenesis, the development of an embryo out of a non fertilized egg.

It happens quite often in the most ancient lines of animals but to the best of my knowledge the last two groups of animals to evolve, birds and mammals, virtually never reproduce by this system, birds very occasionally, mammals, never.

Has anyone ever heard of a mammal who truly produced a clone of itself?

In the past, if this might have ever happened it would have been impossible to ascertain (poor of any woman who would have suffered such an event!). But nowadays it is simple and clear to check any suspicious case and find out the truth.

In my opinion there is an interesting question pending a good answer. Why mammals have lost completely the ability to produce clones of themselves when the absolute majority of the rest of the living world (plants, fungi, other animals, microorganisms) can do so?.

Sorry if im going to far back here, but there was a komodo dragon in the british zoo in england where it produced a baby asexually. Its very interesting how similar birds and reptiles are.. In a book I have there are theories they are related to eachother. I wonder how one sprouted wings, whilst the other had scales/skin.

 

 

As for 27 the first part asks you to sketch a graph of the phenotypes of the population over time. So you could make two line graphs where you plot the number of organisms with one phenotype as one line and the number of individuals for the other phenotype as the other line.

 

 

How do i get the penotypes and population? like what numbers am I using?

2pq does not have to equal 1. The Hardy-Wienberg Equation states [math]p^{2}+2pq+q^{2}=1[/math]. So in this problem B=p=.73. The equation p+q=1 allows ups to find q=1-p=1-.73. Then to find the frequency of heterozygotes we just do [math]2pq=2(.73)(1-.73)[/math]

 

As for 27 could you post the required figure, 14.4?

So if 2pq= 2 (0.73) (1-0.73)

=2 (0.73) (0.27)

= 2 x 0.1971

= 0.3942

so is the answer 0.39 ?

And what exactly do they want me to show for my work?

Now i think i just need help with 27 :\

yep sorry i forgot to add it!

Edit: Added!

Alright for that one the answer for 26 i dont quit understand at all.. Like imagine teaching this too someone whos never done math or bio before and explain in lamens terms and in small steps.

thanks

Alright so basically I'm doing grade 12 U Biology in order to upgrade before heading to college, although im entirely stuck on how to this. I remember doing punnet squares in grade 11 but this just seems a little complex, and the text books really don't help that much.

And here's the questions I am stuck on. I'm totally lost. Like I tried it out and to find 2pq I didnt end up with 1.

26. A population has two alleles, B and b. The allele frequency of B is 0.73. What is the heterozygotes frequency, if the population is in the H-W equilibrium? (10 marks)

Marking guide

• Calculation indicate that heterozygotes frequency, if the population is equal to 2pq in the Hardy=Weinberg equation (2 Marks)
• Substitutes correct number into equation "p+q=1" ( 2 marks)
• Obtains correct result using equation "p+q=1" (2 marks)
• Obtains correct final result (2 marks)
• States the final result in a meaningful sentence (2 marks)

27.

a) Using the data in the data in the diagram provided in figure 14.4 of a theoretical bacterial or insect species, graph the phenotypes of the resistant and non-resistant forms over the three generations a), c), and e).

b ) Calculate the p and q frequencies for each of the three generation's starting populations, assuming the resistant allele is recessive.

Figure 14.4

Marking guide

• Accurately counts and then calculates the percentage of resistant and non-resistant forms in the three generations show in a), c), and e) of figure 14.4 (5 marks)
• Correctly represents data from above calculations in graph form (5 marks)
• Above graph has appropriate labels (1 mark)
• Accuratly calculates the p and q frequencies of all three generations (3 x 3 =9 marks)

Heres the example from the text book