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Ginga-Ninja
Identifying Unknown Ionic Substances?
Hi there, just doing a chemistry experiment in which we are required to identify 4 unknown solutions, using only the solutions provided (i.e. no extra reagents allowed).
They are AgNO3, ZnSO4, BaCl2, NaCl
Through use of standard reaction procedures, it looks fairly easy to identify which solution is AgNO3 and which is NaCl. However, then we are left with BaCl2 and ZnSO4 - how is it possible to determine which one is which?
Any ideas??? Thanx
2 AnswersChemistry1 decade agoTrigonometry Challenge....?
Hey there - quick trig question that will provoke the mind....
Find the exact value of (7sin3x)/sinx - (7cos3x)/cosx
Any ideas??? Help would be much appreciated :D Thx...
3 AnswersMathematics1 decade agoExponentials and Logarithms Question?
Hey there - quick question on exponential eqns (again.......) :D
Here goes...... a radioactive material has a half life of 15 yrs. If 4kg exists now find its rate of change after 10 yrs
Thx - any help would be much appreciated :D
1 AnswerMathematics1 decade agoMaths Counting Techniques and Probability Help!!?
Hey there - quick question here:
A security code consists of four different letters chosen from the 26 in the alphabet, order being important. For example U L E P
a) if one code is created at random what is the probability that it will contain at least one vowel?
b) given the code does not contain any vowels what is the probability that it will contain an X?
Thx - any help will be much appreciated :)
2 AnswersMathematics1 decade agoTrigonometry Challenge - For all those game enough....!!!!?
Hey there - bit of a trigonometry mathematics challenge I found lying around the other day. The question goes:
(On uploaded image)
The diagram shows how the vertical motion of a piston can be used to produce rotational motion. As the piston travels from the low position to the high position and back again the wheel will rotate. If the minor arc PQ is equal in length to r, the radius of the wheel, express x as a percentage of h correct to the nearest percent.
The URL for the diagram is:
http://tinypic.com/view.php?pic=24viu7k&s=4
(Looks like a bit of a challenge to me.... any ideas.... help??) Thx :D
2 AnswersMathematics1 decade agoComplex Numbers Help?
Hey - quick question on complex numbers (again!!) Question goes:
If z = (2-i)/(1+i) - (6+8i)/(p+i) where p is a real number, find the values of p which make the complex number z = x + yi lie on the y =x in the complex plane. Show all reasoning
Sounds like one lot of a question to me.... Any ideas?? Thx :D
1 AnswerMathematics1 decade agoComplex Numbers in Maths?
Hi all - just a quick question with regards to dealing with complex numbers in mathematics.....
Here goes: If a + bi is a root of the quadratic equation x^2 +cx + d =0 show that a^2 + b^2 = d and
2a + c = 0
Any ideas on how I should go about with this question?? Thx :)
2 AnswersMathematics1 decade agoProving Trigonometric Identities?
Hey (again!) - just in the process of proving some trigonometric identities: Questions go:
Prove
tan^4x+tan^2x = (1-cos^2x)/cos^4x
Prove
cos^4x+sin^2x = cos^2x + sin^4x
If anyone could help - would be much appreciated!! Thx :D
4 AnswersMathematics1 decade agoParallel Vectors Help?
Hey bit of a query on vectors at the moment..
The question goes:
Find possible values of h and k if the vectors (h^2i - (3k-1)j) and (4i + (3-k)j) are parallel
(tried making the gradients equal and solving the equation formed, but there are two unknown variables so it doesnt work...)
Anyone with any idea to do this question?? Thx :D
3 AnswersMathematics1 decade agoReaction of Cyclohexene and potassium permanganate to form Mn2+ ions?
Hi there, just a bit of a dilemma here - it would be really good if I could get some help in sorting out the equation where
cyclohexene, potassium permanganate and (water/H+/H3O+ ion) react to form Mn2+ ion, cis-1,2-cyclohexanediol and potassium hydroxide???
help!!!! many thanx if I could get this eqn. sorted!!!!!!!!! :)
1 AnswerChemistry1 decade agoFormatting (background) in a table not displaying on a website?
Hi there - kinda in the process of designing my on website - as opposed to using a CSS layout approach with absolutely positioned layers for text banners and to specify to location of images, I have instead chosen to base the design around a table format - with the different rows and columns inside the table used as the basic text and image locations
I'm design the website in Microsoft Expression Web and am able to set a background image for the cell(s) of the table there, and when the website previews in a browser the cell backgrounds show up ok
Howevery when I upload my website to an online server none of the table cell backgrounds appear
Can anyone help???????? :)
1 AnswerProgramming & Design1 decade agoDHTML menus on a website?
Hey all - kinda in the process of designing my own website - its got some flash content and DHTML menu that I have generated used SoThink DHTML. It seems that when I preview the website I constructed in Microsoft Expression Web in FIreFox of IE7, the DHTML menu displays fine.
However, when I upload my website to an online server and view it through the internet, the DHTML menu does not show up (there is a white blank space where the menu is supposed to appear)
If anyone could help at all - it would be much appreciated!!!
Thanx :D
2 AnswersProgramming & Design1 decade agoTRIGONOMETRY CHALLENGE 2 - HELP NEEDED AGAIN!!!?
Hi there (again for today)
Can anyone please help me proving the following trigonometric identity (its study for an exam I have soon....)
sinx.tanx/2 = 2 -2cos^2(x/2)
Cheers
1 AnswerMathematics1 decade agoTRIGONOMETRY CHALLENGE - HELP NEEDED!!!!?
Hi everyone
Ummm, just a bit of a trigonometry question I'm having some difficulty with.... does anyone know how to do this????
From a point on level ground the angle of elevation of a vertical flagpole is 40degrees. From the same position find the angle of elevation of the point three quarters of the way up the flagpole.
The answer is 32degrees, but however we are supposed to get there Im not sure.....
Help would be MUCH appreciated!
2 AnswersMathematics1 decade agoConverting polar equation to Cartesian equation?
Hi there!
I'd be great if anyone could kindly help me with the following problem that im having some troubles with.
Can you pls demonstrate how to convert the polar equation:
r = 2cos3θ into a cartesian equation?
thanks, help will we be much appreciated!!!!!!!!!!!!
:-)
4 AnswersMathematics1 decade agoGraphing circle equations on Ti nspire calculator?
Hi (esp. to anyone who has experience with a graphics calculator, or even better the ti nspire).
I'm doing some work in maths, and was wondering if there was a way to graph circle equations, such as:
(x-3)^2 + (y-2)^2 = 9
or x^2 + y^2 = 16
on a graphics calculator (esp. ti nspire)
many thanks,
help will be much appreciated!! :D
1 AnswerMathematics1 decade agoHow Carbon In steel changes the properties of iron?
Hi there - just some chemistry assignment help....
Hey I was wondering if anyone could help me on an explanation of how the amount of carbon in steel changes the properties of iron. I know that the carbon fit into the Fe's crystal lattice, but are there any different ways of explaining it, or visualising how the carbon atoms fit in?
Thanx :-)
4 AnswersChemistry1 decade agoNaCl and NaOH dissolved in water?
Hi - just need some help in chemistry:
In the solid state both NaCl and NaOH are ionic lattices. What happens to these substances when they dissolve in water?
Thanx
5 AnswersChemistry1 decade agoIonic and Covalent Bonds in Common Substances?
Hi there - (back again...) I'm just doing some chemistry homework, and was just considering how different substances, e.g. sodium hydroxide have ionic bonding between the atoms, while pure hydrogen chloride has a covalent bonding system. Is there a way that I work out whether a certain compound has ionic or covalent bonding?
Is it something do with metals and non-metals forming ionic compounds?
Thanks!!
1 AnswerChemistry1 decade agoPhysics - Ball thrown upwards returns to its starting point in 4 seconds?
Hi there (so tired :P)
Yeah, anyway I've got this Physics question that I'm having some difficulties with (probs cause I'm just about exhausted).
It reads:
A ball thrown vertically upwards returns to its starting point in 4 seconds. What is its initial velocity?
Thanks in advance!! You'll be a real help (gee I must be real tired aye...)
5 AnswersPhysics1 decade ago