Science & Mathematics - 18 October 2007

using knowleged of atomic structure why is the reaction of calcium with water less vigourous than that of radium and water

2007-10-18 10:28:38 · 1 answers · asked by Anonymous in Chemistry

Need an answer quick???? Pretttty please wit da cherry on top!!!!!!!!!!!!!!

2007-10-18 10:28:33 · 1 answers · asked by CuriousCat 1 in Earth Sciences & Geology

2007-10-18 10:27:46 · 17 answers · asked by little devil 4 in Biology

2007-10-18 10:25:47 · 1 answers · asked by Anonymous in Chemistry

I have one problem. I understand how to "verifying," but I am completely puzzled with this one. I have spent atleast 15 minutes on this problem and have not gotten anywhere.

1) 1-cos/1+cos = (cot - csc)(cot - csc)

Again, this is a verifying problem.
Please, I would really appreciate some help here...thanks!!

2007-10-18 10:25:29 · 5 answers · asked by Anonymous in Mathematics

2007-10-18 10:24:07 · 8 answers · asked by ? 1 in Astronomy & Space

2007-10-18 10:23:03 · 2 answers · asked by Anonymous in Geography

in organic or biochemistry

2007-10-18 10:22:56 · 1 answers · asked by PrtbD 1 in Chemistry

2007-10-18 10:21:09 · 13 answers · asked by my4sweets 1 in Chemistry

Yeah, if you could do me the biggset favor and either explain HOW to balance chemical reactions, give me a site that explains(i cant find any) or maybe answer these?
'Write out the reaction and balance
1. Copper (II) Nitrate + Sodium hydroxide
2. Copper (II) Hydroxide + Heat
3. Copper (II) Oxide + Hydrochloric acid
4. Aluminum + Copper (II) Chloride
5. Aluminum + HYdrochloric acid'


I am so incredibly lost. Any help would be highly appreciated, please? :(

2007-10-18 10:19:01 · 1 answers · asked by Tessaaa 2 in Chemistry

A 2.00 kg block situated on a rough incline is connected to a spring of negligible mass having a spring constant of 100 N/m (Fig. P5.76). The block is released from rest when the spring is unstretched, and the pulley is frictionless. The block moves 21.2 cm down the incline before coming to rest. Find the coefficient of kinetic friction between the block and incline.

link: http://www.webassign.net/sf/p5_76.gif

help pleasee

2007-10-18 10:18:47 · 1 answers · asked by Anonymous in Physics

A child's pogo stick (Fig P5.75) stores energy in a spring (k = 2.40 104 N/m). At position A (x1 = -0.100 m), the spring compression is a maximum and the child is momentarily at rest. At position B (x = 0), the spring is relaxed and the child is moving upward. At position C, the child is again momentarily at rest at the top of the jump. Assume that the combined mass of child and pogo stick is 27.0 kg.

link: http://www.webassign.net/sercp/p5-75.gif

(a) Calculate the total energy of the system if both potential energies are zero at x = 0.

(b) Determine x2.

(c) Calculate the speed of the child at x = 0.

(d) Determine the value of x for which the kinetic energy of the system is a maximum.

(e) Obtain the child's maximum upward speed.

2007-10-18 10:17:04 · 1 answers · asked by Anonymous in Physics

just wondering

2007-10-18 10:17:01 · 2 answers · asked by Anonymous in Physics

OK iM NOT KIDDING IM TALKING MILLIONS LIETTERALLY?????? Here's the deal 11 story highrise, with 30 apartments per floor this morning anyone with opened windows woke up with their house full of 100's in some cases 1000's of ladybugs now. All the balconies are full all that could be seen is blankets of the bugs all over them and 1000's flying around the building Im the manager and people are comming home now and freaking WHAT IS GOING ON ? HOW IS THIS POSSIBLE AND WHAT DO I DO

2007-10-18 10:15:58 · 14 answers · asked by Anonymous in Zoology

Science question

2007-10-18 10:15:56 · 3 answers · asked by Thatsnotmyname. 2 in Weather

I'm just beginning my studies in Electronics Engineering Technology and I have an assigment to research digital multimeter. Any experienced electronics engineers out there to help. Thank You!!

2007-10-18 10:15:52 · 4 answers · asked by Supa_Sexy1 2 in Engineering

2007-10-18 10:14:27 · 9 answers · asked by THE WALL 1 in Geography

I want to ask to questions but not use up 10 points.

Question #1
Work in physics is defined by one moving an object. My question is how is doing no work even possible, when just by standing at rest on (lets say) a floor we are bending it. The molecules in the floor are moving, so aren't we in fact doing work? Isn't bending something the same thing as doing work because there is movement on the molecular level? Please explain this if you can because I'm confused.

#2. can some energy be lost as it converts from one form to another(i.e. light to heat). The two forms are made of different properties, but would the mass of heat be equal to the mass that the light had? If yes, how can it if the properties are different. Basically how can energy go from one state to another without loosing part of itself as its properties change during conversion.. I mean you have to lose and gain something to change right? Is lost energy the same thing as destroyed.

I know there is error in my thinking

2007-10-18 10:12:30 · 3 answers · asked by Anonymous in Physics

2007-10-18 10:10:11 · 29 answers · asked by Anonymous in Biology

Can't figure out, how lightening operates i.e from ground to sky as people say or from the sky to the earth - as it looks.

I am aware that people have electric inside their bodies, which may help them tolerate such strikes, do tree's have none?, at all?
I'm stumped over this one.
Thanks

2007-10-18 10:09:52 · 5 answers · asked by John S 1 in Weather

using conservation of momentum and energy what is the velocity of the slower object after the collision and what is the velocity of the faster object after the collision?

2007-10-18 10:08:45 · 2 answers · asked by amy b 1 in Physics

It was desired to neutralize a certain solution X that had been prepared by mixing solutions of potassium chloride and hydrobromic acid. Titration of 10.0ml X with 0.100 M silver nitrate required 50.0ml of the latter. The resulting precipitate, containing a mixture of AgCl and AgBr, was dried and found to weigh 0.762g. How much 0.100M sodium hydroxide should be used to nuetralize 10.0ml of solution X?

2007-10-18 10:07:27 · 1 answers · asked by jrb229 1 in Chemistry

1. A body ........................... is a group of organs that work together to do a job.

2. .................................... tissue is tissue that covers and protects the body.

3. Tissues combine to form................... ...

4. ................... Cells are the cells that make up complex organisms.

5....................... tissue that covers and protects the body.

6. all the activities that take place in a cell take place in the ............................


can anyone help me on this?

2007-10-18 10:07:17 · 1 answers · asked by whitefire 2 in Botany

2007-10-18 10:07:14 · 4 answers · asked by New Mommy 1 in Astronomy & Space

also.
______blank______ in the soil and in nodules on roots of some plants change or ____blank____ most of nitrogen gas.

please help.

2007-10-18 10:06:14 · 1 answers · asked by Elisabeth B 1 in Botany

$500 to grow to $1,039.50 if invested at 5% interest compounded anually

I atleast need the formula
thanks

2007-10-18 10:06:07 · 2 answers · asked by Luby 5 in Mathematics

Need help!

2007-10-18 10:05:40 · 5 answers · asked by Anonymous in Mathematics

Please explain why. you think this.

Make the answer simple.

Thnx!

2007-10-18 10:04:56 · 9 answers · asked by Someone 2 in Mathematics

if any of the enormous volcanoes on mars erupted, what would happen to planet earth and some of the other planets in the solar system?

accurate answers please!!

2007-10-18 10:01:15 · 6 answers · asked by dancerbabe311 2 in Astronomy & Space

2007-10-18 10:00:42 · 17 answers · asked by rynoxmanedge 1 in Mathematics