mercuryv8

That's what I was looking for. Thanks Nic

I can recomend "Chemical Demonstrations: A handbook for teachers of Chemistry" v.1 and v.2 written by Bassam Z. Shakhashiri ISBN 0-299-08890-1 (v.1) ISBN 0-299-10130-4 (v.2) A must for any Chemistry teacher

I'm a teacher. Thanks for the discussion, The solution to the problem is the easy part. The person that asked the question was looking for more of a theory behind solving the problem answer. I've worked out a system of equations to help. Nic

I see what you are saying. It would make more sense if they specify what the costs of each are. Opps!! sometimes I sould spend more time reading. The Cost of sunflower seeds is .12$ per unit and raisins are .10 $ per unit Nic So 5:5 must be the optimal mixture. You get 75g of Fiber 30mg of Iron and the cost is 1.10$ / 1000g

A coworker of mine phoned with this problem. You have been asked to create at least 1000g of a mixture of sunflower seeds and raisins. The mixture must contain at least 75g of dietary fibre, but no more than 40mg of iron. Use the chart below to determine how many units of sunflower seeds (1 unit is 100g) and how many units of raisins (1 unit is 100g) should be used to minimize the cost of producing this mixture. Dietary fibre (g) 10 g / unit sunflower seeds Dietary fibre (g) 5 g / unit of raisins Iron (mg) 4 mg / unit Sunflower seeds Iron 2mg / unit raisins I’ve worked out a system of e equations, and have tried to graph the problem. But I don’t know what the best strategy is. Thanks for any input . Nic

That's great!

Molar mass of NaHCO3 Na = 22.99g/mol X 1 H = 1.01g/mol x1 C = 12/02g/mol X1 O = 16.00g/mol X 3 Molar mass NaHCO3 = 84.02 g/mol (1mol / 84.02g) * 10.17g = 0.12 Moles NaHCO3

What's in the aqueous solution when you expose them to sunlight? Nic

That's not flash powder...flash powder still needs an source of ignition. Perhaps it's something like floured magnesium or aluminum? Nic

Yeah? And thanks for your help with the factoring of the equation...It makes more sense now. Nic

The title for this post is inappropriate sorry, I hit post when I should have hit preview. I'm trying to re-arrange the first equation in the series below to the format [math] y=a(x-p)^2+q [/math] Using the completing the square method, now I have a process down where I get the right answers. But I don't understand what happens to the "8x" them in the last step...I just leave it out and take the sqroot of the "16" and the "x^2" to get the (x-4) in brackets? I don't fully understand why one-half of the coefficien of the x-term is added and subtracted either? [math] F(x) = 3x^2-24x+40 [/math] [math] F(x) = 3(x^2-8x)+40 [/math] [math] F(x) = 3(x^2-8x+16-16)+40 [/math] [math] F(x) = 3(x^2-8x+16)-48+40 [/math] [math] F(x) = 3(x^2-8x+16)-8 [/math] [math] F(x) = 3(x-4)^2-8 [/math] any help in explaining this to me is greatly appreciated. Thanks in advance Nic

Yeah I messed up when I was solving the equation...subtracting a negative number. Shouldn’t be doing quadratic work before I have a handle on adding and subtracting integers eh! Monday is my excuse! Thanks Yes typo in my first post...sorry [math] y=x^2-2x-5 [/math] Nic

So I have the equation y=x^2 - 2x-5 I graphicaly determine the zeros to be 3.45 and -1.45...shouldent I be able to substitute these values in for x and solve the equation...which should be zero. 3.45 gives and answer near zero 0.0025 (perhaps rounding error) but -1.45 is nowhere close. What's the deal? Nic

Can't help you on the books...but years ago I watched a discovery channel documentary on ancient tech...it was facinating. I really enjoyed the encription techniques used long ago. Try their website, maybe you can find it. Nic

My wife and I don't have a T.V. Not many people can say that. I watched lot's of T.V when I was in High school. I don't really miss it at all, there are so many other things to do I don't know how I would have time to watch. My wife and I play games, dice (10000) is our fav. I don't think we can hold a conversation any better than our friends though. Nic