Science & Mathematics - 12 November 2006

2006-11-12 20:47:01 · 3 answers · asked by Anonymous in Mathematics

Small quantities of oxygen gas are sometimes generated by heating KClO3 in the presence of MnO2 as a catalyst:



2KClO3(s) → 2KCl(s) + 3O2(g)



What volume (ml) of O2 is collected over water at 24.0 oC by the reaction of 0.285 g of KClO3 if the barometric pressure is 729.9 mm Hg
The vapor pressure of water at 24.0 oC is 22.4 mm Hg.

2006-11-12 20:43:55 · 1 answers · asked by Whatever 1 in Chemistry

2006-11-12 19:45:20 · 3 answers · asked by manojkp76 1 in Geography

2006-11-12 19:37:29 · 4 answers · asked by Anonymous in Geography

I am trying to do the problem below but I don't understand how to do it. Can you please show me how to do it? DON'T give me the answer, explain to me how to get the answer.

Figure: http://img134.imageshack.us/img134/9168/untitled1au7.jpg

Point C moves at a constant rate along semicircle centered at ) from A to B. The radius of the semicircle is 10 cm, and it takes 30 sec for C to move from A to C. Angle COB has measure y radians, angle OCA has measure z radians, and AC = x cm as indicated in the figure.

a) What is the rate of change, in radians per sec, of x with respect to time?

b) What is the rate of change, in radians per sec, of y with respect to time?

c) x and y are related by the Law of Cosines; that is, y^2 = 10^2 + 10^2 - 2(10)(10)cos y. What is the rate of change of x with respect to time when y = π/2 radians?

d) Let D be the area of ΔOAC. Show that D is largest when x = π/2 radians.

2006-11-12 19:33:38 · 1 answers · asked by WiseG 1 in Mathematics

2006-11-12 19:30:02 · 15 answers · asked by Anonymous in Biology

like do they become really smart when they grow up

2006-11-12 19:21:21 · 5 answers · asked by Ry126 3 in Other - Science

2006-11-12 19:21:10 · 9 answers · asked by Xa!ny 2 in Physics

2006-11-12 19:19:06 · 9 answers · asked by sourabh k 1 in Earth Sciences & Geology

It is the largest bat in the world

2006-11-12 19:08:07 · 3 answers · asked by Dj 1 in Zoology

2006-11-12 19:06:41 · 3 answers · asked by Anonymous in Engineering

can you pls help me me here are the questions:
1. what is physics?
2. what are the sub - area of physics?
3 how phsics help in technological developments?

2006-11-12 19:06:38 · 6 answers · asked by Anonymous in Physics

This lemur is found in the west as well as in the north of asia.

2006-11-12 19:03:20 · 2 answers · asked by Dj 1 in Biology

2006-11-12 18:58:08 · 6 answers · asked by flavorlicious 2 in Zoology

The flywheel of a steam engine runs with a constant rotational velocity of 150 rev/min. When steam is shut off, the friction of the bearings and of the air stops the wheel in 2.2 h.

(a) What is the constant rotational acceleration, in revolutions per minute-squared, of the wheel during the slowdown? (b) How many rotations does the wheel make during the slowdown?

(c) How many rotations does the wheel make before stopping?

(d) At the instant the flywheel is turning at 75 rev/min, what is the tangential component of the translational acceleration of a flywheel particle that is 50 cm from the axis of rotation? (e) What is the magnitude of the net translational acceleration of the particle in (d)?

Can you explain your answers, and show the equations you used to solve this?

2006-11-12 18:57:43 · 2 answers · asked by Anonymous in Physics

2006-11-12 18:57:31 · 1 answers · asked by puppy 1 in Engineering

The flywheel of a steam engine runs with a constant rotational velocity of 150 rev/min. When steam is shut off, the friction of the bearings and of the air stops the wheel in 2.2 h.

(a) What is the constant rotational acceleration, in revolutions per minute-squared, of the wheel during the slowdown? (b) How many rotations does the wheel make during the slowdown?

(c) How many rotations does the wheel make before stopping?

(d) At the instant the flywheel is turning at 75 rev/min, what is the tangential component of the translational acceleration of a flywheel particle that is 50 cm from the axis of rotation? (e) What is the magnitude of the net translational acceleration of the particle in (d)?

Can you explain your answers, and show the equations you used to solve this?

2006-11-12 18:55:37 · 2 answers · asked by Anonymous in Mathematics

In theory if you traveled in a circle fast enough there would be a point when you arrived at the depature point before you left it?

2006-11-12 18:55:37 · 18 answers · asked by ANON 4 in Physics

2006-11-12 18:44:49 · 7 answers · asked by bobken 2 in Botany

1)speed
2)velocity
3)force
4)acceleration

2006-11-12 18:39:54 · 8 answers · asked by Anonymous in Mathematics

2006-11-12 18:32:30 · 6 answers · asked by Guru 1 in Biology

plz help me... plz

2006-11-12 18:32:05 · 1 answers · asked by the cool guy 1 in Chemistry

why do you get used to the weather of where you're living-- what physiological changes happen that make you used to whatever weather temperatures are?

2006-11-12 18:31:36 · 4 answers · asked by misterlyle 3 in Biology

2006-11-12 18:27:53 · 4 answers · asked by Anonymous in Botany

a concrete mix requires 3 parts sand and 5parts cementhow many pounds of cement are neede for 75 pounds of sand?

2006-11-12 18:27:40 · 4 answers · asked by ls1boi 1 in Engineering

is the fourth??????

How can time be a dimension, how can anything.

Just say that you have a cardboard box, everything in that box is air and empty space, how can there be more than one dimension, what is a dimension, it it made of matter??? (I'm a biologist, not a physicist)

Also, what is time, I don't believe there is a force regulating the movement of molecules and atoms, if we never even contemplated time then nothing would be any different, because batteries make a clock tick, which measures how long until the end of the day. Time isn't a force. Or is it?

2006-11-12 18:24:57 · 9 answers · asked by Anonymous in Physics

Do you think time travel is really possible? Why? How?
Will appreciate your answers!

2006-11-12 18:24:02 · 11 answers · asked by ray b 1 in Astronomy & Space

2sinx+3=4 domain is 0<=x<= pi/2

2006-11-12 18:22:37 · 6 answers · asked by John 1 in Mathematics

only one of my friends can solve it (none of my friends are mathematical, though)

x + y + z =1

using only that fact, prove:
xy + yz + xz < 1/2

2006-11-12 18:22:19 · 6 answers · asked by Jason D 2 in Mathematics

When a thermometer is affected by heat or cold is it physics at work or chemestry at work?

Thanks for your help scientists and teachers.

Jimmy

2006-11-12 18:21:18 · 6 answers · asked by Jimmy The Hand 5 in Other - Science