ChemSiddiqui

Is there are particular approach to nanotechnology about which you are especially curious, Chemsiddiqui?

Sure, I was particularly impressed by nanotubes which I found to be of great importance in the future. Like drug delivering for example. If any one can discuss how this is done and what is the mechanism, I think i'd like that.

"without any environmental influences"? Oh dear Lord. Please tell me how that works.

 

"Might I suggest that we keep this thread for information basis about Nanotechnology Only"

 

"information" or mis"information"?

I did not realize this was a promotional segment. I surrender.

I'm going to eat a 3 bowls of fruit loops with extra sugar and watch the National Geographic Channel. Then it's off to the beach to stick my head in the sand and try to unlearn the years I've spent studying and practicing chemistry, pharmacology, biology, and quote unquote "nanotechnology". Maybe then I can get with the program.

 

In passing, I would like to add that this thread is in General Chemistry. Therefore, if whatever you, I, or anyone else have to say about "nanotechnology" holds water, it should be able to withstand the test of objective scientific discourse from all angles (including positive and negative....the laws chemistry and physics, environmental, toxicological, physiological aspects, etc etc). If not...well, then it may not.

O alright, alright. I was merely suggesting to keep this disscussion friendly! but I must admit i found your comments rather funny (no offence! ). I also confirm that i am not ridiculing your experience with chemistry work, which i am sure would be great!. But its my personal opinion as i read a lot of ChemistryWorld magazine published by the Royal Society of Chemistry, that nanotechnolgy has a future that human can benefit from. Good day!

uh-huh, alright then thnx very much. I'll just try to practice some more questions and see what happens. Thanks again!

Just to make one important point clear and to reduce confusion: You understand that the way you approached the problem is correct and that if you don't screw up the numbers when applying the quadratic formula you will get 1 correct solution, are you? So you have solved at least part of the problem

Yes, you are right. I am weak in maths and can't understand things unless I am face to face with whoever is instructing me.

The problem is that what I said already was on the borderline of what I consider appropriate for helping with homework.

Sorry if i gave the wrong impression but this is no homework. I didn't ask to work things out for me, I know I have to do it myself. I only wanted help! however I thank you for your help! I really appreciate it.

- On b² you forgot to square and put 5 instead of 5²=25.

- I hope you understand why your calculator gives an error for .

- does not map on the whole range -180° <= phi <= 180°. You might (you do) miss solutions. Not exactly sure how you get the 2nd solution (you did make a sketch/plot to see that there's two solutions, did you?). I'd try by reexpressing x=cos(phi - 90°) rather than x=sin(phi).

On b² you forgot to square and put 5 instead of 5²=25.

I think then x = 0.175 or -1.425. SO if I take the inverse of tan the phi will be 9.926 and -54.94 respectively.

- I hope you understand why your calculator gives an error for .

I do yes!

does not map on the whole range -180° <= phi <= 180°. You might (you do) miss solutions. Not exactly sure how you get the 2nd solution (you did make a sketch/plot to see that there's two solutions, did you?). I'd try by reexpressing x=cos(phi - 90°) rather than x=sin(phi).

 

I have no clue whatsoever what it means or to do next or how to find the answers out .

I happened to look at his pos and just want to clear something. Antilog of x is actually 10 ^x .

Hi all,

This is my first post in this section of the forums!

I was doing some past papers and I am stuck in this question. Need help any1.I am not very good at maths! I am doing A’ levels by the way.

Q. Solve the equation for angle in the range -180 ≤ Ф ≤ 180.

4 Cos2 Ф + 5 Sin Ф = 3

My solution is:

4 (1- Sin 2 Ф) + 5 Sin Ф -3 = 0.

4 – 4 Sin 2 Ф + 5 sin Ф -3 = 0.

-4 Sin 2 Ф + 5 sin Ф = 0.

Assuming sin Ф = x, then

-4x2 + 5x + 1 = 0.

Using quadratic formula:

x = -b -+ √ b2 – 4ac

2a

x = - 5 -+ √ 5 -4(-4)(1)

-8

So x = -5 – 4.58

-8

x = 1.197

OR

x = -5 + 4.58

-8

x = 0.0525

Now I have 2 values of x which I am going to replace in sin Ф = x

So Ф = Sin -1 1.197 ( calculator says Ma error)

We have one x value left which I am going to put now:

Ф = sin -1 0.0525

= 3.009 or 3.01 ( 3 significant figures and 2 decimal places).

I know that sin is always positive in the first and second quadrant but I have never managed to get the answers! Anyone can tell me what to do now or what mistake have I made?

I’ll really appreciate it thnx!

Might I suggest that we keep this thread for information basis about Nanotechnology Only. True there are shortcomings with this field because its relatively recent branch of science. but, we will see good about it. As i just learnt that the nanotubes can be used to perform complex reaction without any environmental influences like air toxication etc they can be highly useful for coming generation of scientists because it will make future reactions whatever they may concern very effective!

problem with nanotechnology is that it has become a bit of a buzzword, similar to "systems biology". It lacks a coherent, stringent definition. In principle you can put so many things from different disciplines into that word so that it might essentially become (almost) meaningless (it just has to be small). In the few posts in this thread we have already seen examples of it. I could add plenty from the direction of biology and biochemistry. In scientific terms it is something under which you submit your grant application, if funds are available and you work with smallish things...

I think you may be right about it but you did admit that it has several uses. I think nanotech is still incomplete, it still needs people to make more inroads in jt. I just want this thread to explain what actually is nanotechnology so that those who are unaware of it should notice its importance.!

The buckyball can be used as a cage to preserve watse. So, nanotechnology can be used to solve this problem as well.

Hi all,

Alright, I am going to start a whole new thread and hope that you people will chipp in with your views about this very hot topic of today's world.

"What is Nanotechnology? What future is there for it and how can it help to change our lives?"

Lets start this dicussion. I thought of this because I think nanotechnology should be discussed on a wider scale.

It is defined as " small science with large benifits". Nanotechnology is the study of materials as small as 10^ -9. Its first was discovery with the finding of Buckministerfullerene or simple bukyball, the 3rd allotrope of carbon.

well thats all I know for now. I will come back with more facts maybe even more interesting ones. In the mean time you also do the same.

Well I think one has to ask a farmer really. Maybe its true but seriously If were to check whether I can smell cyanide I cut that option from my list of tests, if you know what I mean!

WOW! I thought this question was a dull one and that it would produce less answers than any of ones posted earlier by me. Its not the case here tough!. I think every1 is inquisitive for knowledge here. O HAIL CHEMISTRY and GOOD POSTERS!

Hi,

I was taking a lecture when a lad came into the class and asked my chemistry teacher a question. I happened to listen the question and wondered what the answer could be :

" Water is a polar molecule. Sugar dissolves in water when its organic compund. Why?"

Strange question I know but whats important is to answer it. I thought that the sugar molecule must have either OH or H groups exposed to water when added to water so that it makes a H-bond with it and dissolves but I think I am not right:embarass: ! Any thoughts any one!

Ok, I want to home-test whether I can smell cyanide but have no access to laboratory cyanide neither do I want one. Does anyone have any idea how to test it then?

I`m also a smoker, so it`s possible that if I Didn`t that I wouldn`t be able to smell it very well at all!

If the gene is dominant in your characteristic I think it won't matter if you need to be a smoker to smell it. Anyway its just a guess!

Hi,

I started reading a novel called 'Cause of Death' by partica Cornvell. And in that novel Dr.Kay Scarpetta quotes:

" the ability to smell cyanide is a rex-linked recessive trait that is inherited by less than thirty percent of the population"

Now I want to know how true this is? Can anyone here smell literally smell cyanide?

Don't most DVDs come with a subtitle feature?

They do, but most of them don't have the option for which language you want them. Like the one I bought the other day had hebrew subtitles and no options. Crazy isn't it?

yes I know, however I wanted to ask was it beacuse of the coiled structuer?

Hi all,

Anyone here can tell me any link to a website which provides free, non-downloadable movie subtitles. The subtitles should not use any software.

Any 1 please!

Hi all,

God has created human beings in complex and complicated ways that It is difficult to imagine anything like it. If i am not mistaken, hair and skin of humans are tertiary proteins. They are insoluble so they dont dissolve in water when we go for a swin or take a bath. I want to ask why is this! My take on this is that it has a coiled structure and from the inside are the intermolecular forces, hydrogen bonding, disulphide bonds and others. From the outside there are no hydrogen bonds which is why its insoluble.

Why do you people think!

Well thank you all, I think I understand it some what now. You were a good help, all of you. thanks again!

No, i am quite sure its isolated atom. here is an abstract from wikipedia:

"

Isolated atoms

Atomic physics always considers atoms in isolation - i.e. a model will consist of a single nucleus which may be surrounded by one or more bound electrons. It is not concerned with the formation of molecules (although much of the physics is identical) nor does it examine atoms in a solid state as condensed matter. It is concerned with processes such as ionization and excitation by photons or collisions with atomic particles.

While modelling atoms in isolation may not seem realistic, if one considers atoms in a gas or plasma then the time-scales for atom-atom interactions are huge in comparison to the atomic processes that we are concerned with. This means that the individual atoms can be treated as if each were in isolation because for the vast majority of the time they are. By this consideration atomic physics provides the underlying theory in plasma physics and atmospheric physics even though both deal with huge numbers of atoms.

Additionally, the properties of an atom in isolation is different from that of individual atoms in relatively close proximity to each other. This is because medium and long range forces come into play with proximity. "

can some1 explain now Please, i can't still get it in my head.

No worries Physia. Mind whatever you hear from me would be my personal but yet authentic account. Things today have been quite ok, its half past 3 afternoon here and the daily life seen to have come to track after 3 after days of difficult situation. hope this news suffices for the time being

Hi all,

I was just curious to know two things:

A. What actually is an 'Isolated' atom?

B. How was this name given?

I am not sure but I think isolated atom is an atom which is inert and in ground state.