Science & Mathematics - 21 November 2007

What countries have the Ukrainians made alliances with?

2007-11-21 10:09:00 · 1 answers · asked by Anonymous in Geography

just trying to see what it becomes when all platinum group metals are combined does it become a new alloy or what does it have a name is it of any use

2007-11-21 10:07:09 · 1 answers · asked by pryze 1 in Chemistry

AgNO3 + Na2 CO3 -> Ag2 CO3 + 2 NaNO3

2 AgNO3 + Na2 CO3 -> Ag2 CO3 + 2 NaNO3

4 AgNO3 + Na2 CO3 -> 4Ag2 CO3 + 2 NaNO3


Choose the answer that shows a correctly balanced equation.

Ni(NO3) 2 + 2 NaOH -> Ni(OH) 2 + 4NaNO3

Ni(NO3) 2 + 2 NaOH -> Ni(OH) 2 + 2 NaNO3

Ni(NO3) 2 + NaOH -> Ni(OH) 2 + 2 NaNO3


Choose the answer that shows a correctly balanced equation.

2 Mg + O2 -> 2 MgO

2 Mg + 2O2 -> 2 MgO

3 Mg + O2 ->3 MgO

Choose the answer that shows a correctly balanced equation.

2Cu + 3 AgNO3 -> 2 Ag + 2Cu(NO3) 2

4Cu + 2 AgNO3 -> 4 Ag + Cu(NO3) 2

Cu + 2 AgNO3 -> 2 Ag + Cu(NO3) 2

2007-11-21 10:03:06 · 3 answers · asked by xlhollisterboi 1 in Chemistry

I have always been interested in electronics and mechanical things, or at least felt a strong connection to technology, but it hasn`t necassarily become a part of my life. I mean, I asked my mom to buy me a Mindstorms set a couple years ago, and I ended up not liking it. Because of my interest I took an inventor`s class where you built contraptions based on physics principles, but I hadn`t enjoyed that either. I love reading about how things work and collecting things like cogs and gears and basically whenever someone mentions "internal combustion engines" I am immediately intrigued. I will admit it: I have fallen in love with an electrical appliance before, I have spent hours at a time taking apart a computer keyboard, and I have snuck into the Tech-ed department(even though I wasn`t supposed to be there) just to look at the tools and inventions other students had made. What`s wrong with me?? Who am I kidding- I hated working with tools. I`m not a "mechanical" person.

2007-11-21 10:00:05 · 5 answers · asked by Anonymous in Engineering

i have homework to do and these questions are puzzling me. im not so much interested in the right answers as the method of finding them.

theres just too many new words flying around at the minute for me, so im confused with this stuff. can anybody help with the following questions? if not all of it then some of it?

i know what the sine and cosine rules are though.

at 18:00 on october 25th:
Venus had right ascension 17h 11m 41s and declination -21 degrees, 8.1'
The Sun has right ascension 14h 0m 53s and declination -12 degrees 18.7'

how do i find what azimuths does venus rise and set on the 25th of october, as seen at greenwich (latitude 51 degrees, 28.6')????

also, how do i find the hour angle when it rises and sets, and the apparent solar time at greenwich when venus rises & sets?

2007-11-21 09:59:53 · 3 answers · asked by fpa06mr 5 in Astronomy & Space

... in the electrolysis of AgNO3 (aq)?
a. 0.807
b. 48.5
c. 0.442
d. 3.23
e. 1.61

THank you

2007-11-21 09:59:49 · 1 answers · asked by Ciso101 2 in Chemistry

2007-11-21 09:59:20 · 7 answers · asked by west.ham_utd 1 in Weather

I am curious to know what is the most common crab species in the USA. Any answers will be greatly appreciated!

2007-11-21 09:59:14 · 3 answers · asked by Golden Retriever Lover 1 in Zoology

This is the assignment.
Measure the height of your computer monitor to the nearest tenth of a centimeter or sixteenth of an inch. Measure the width of your monitor as well. Use the Pythagorean Theorem to find the length of the diagonal of your monitor. How do I measure it the the sixteenth of an inch? And how would I apply the Pythagorean Theorem to this?

I found the height which is 14 inches
The width is 15.5 inches

2007-11-21 09:57:10 · 5 answers · asked by cupnnas2002 3 in Mathematics

MnO2 + NH4 --------> Mn2O3 + NH3 + H2O.

2007-11-21 09:53:44 · 2 answers · asked by xlhollisterboi 1 in Chemistry

when I make instant coffee (or hot chocolate), stir the milk and sugar in and tap the spoon on the rim of the mug, for about 10-20 seconds, the note that the tapping makes rises in pitch.

If I then restir the it, the resonant note deepens, and again rises when I tap on the rim.

this behaviour does not happen with:
(a) a cup of plain cold water,
(b) a cup of plain hot water,
(c) nor even a mug of cold water containing instant-coffee solids
(d) nor a mug of hot tea.

it happens only when it is both hot and contains instant-coffee or cocoa (hot chocolate) solids.

can anyone explain this phenomenon?

2007-11-21 09:51:50 · 1 answers · asked by Anonymous in Physics

Is it becuase uranium mining is cheap? why would uranium mining be cheap?

2007-11-21 09:47:46 · 6 answers · asked by joy 3 in Chemistry

2007-11-21 09:43:17 · 1 answers · asked by Anonymous in Chemistry

How many grams of vegetation would an active common garden snail be expected to eat each day/week?

2007-11-21 09:42:36 · 5 answers · asked by Anonymous in Zoology

seeing ghosts but not schitzophrenic or insane. no psychological disorder

2007-11-21 09:42:27 · 4 answers · asked by yejin 2 in Paranormal Phenomena

both numbers 2 are exponents

2007-11-21 09:41:41 · 3 answers · asked by Anonymous in Mathematics

okk
if the percent is 5 1/4 well then what is the fraction and the decimal
and if u would please show me how to work this out

thanks

2007-11-21 09:41:40 · 7 answers · asked by Anonymous in Mathematics

2007-11-21 09:37:34 · 6 answers · asked by Heyy!!! 1 in Chemistry

How would you express this quadratic expression x^2-(2√3+1)x+2√3 in factored form using the quadratic formula?

The answer is (x-2√3)(x-1). Could anyone show me the process work?

2007-11-21 09:35:37 · 5 answers · asked by Adrift 2 in Mathematics

Abbie is an interior designer who has been asked to find an oriental rug for a new corporate office. As a rule, the rug should cover 1/2 of the total floor area with a uniform width surrouding the rug. If the dimensions of the room are 12 feet by 16 feet, find the dimensions of the rug that Abbie should look for.


I'm having so much trouble with this problem, I did it like 10x times and kept on getting different answers! Please explain it step by step if possible thanks!

2007-11-21 09:34:20 · 6 answers · asked by CLUELESS! 1 in Mathematics

I'm thinking of an original reason of why go to space, please help me with this biology HW!

2007-11-21 09:34:05 · 16 answers · asked by Top Contributor 3 in Astronomy & Space

geology sec.

2007-11-21 09:33:45 · 3 answers · asked by Jaleyna S 1 in Earth Sciences & Geology

find the area of the figure and the figure look likes a straight rectangle and from the left side some space is cutted and the rectangle has three demensions and one is missed

2007-11-21 09:31:46 · 2 answers · asked by Anonymous in Mathematics

A hole is drilled through uniformely dense Earth, from North to South pole.
Four clocks were syncronized at North pole.

One clock A was dropped into the hole and reappeared 84 minutes later.
Clock B was launched into low polar orbit, and landed at North pole 84 minutes later.
Clock C was fired upward with carefully chosen inital velocity, and landed simultaneously with A and B 84 minutes later.
Clock D remained at rest at North pole.

Which clocks are ahead and which are behind?
(Note that A,B and C remained in free fall and followed geodesic lines)

2007-11-21 09:23:37 · 3 answers · asked by Alexander 6 in Physics

which of the following is a TRUE statement? (A) it is possible to transfer heat from a cooler to a hotter body. (B) it is possible for heat to flow spontaneously from a hot body to a cold one or from a cold one to a hot one, depending on whether or not the process is reversible or irreversible. (C) the second law of thermodynamics is a consequence of the first law of thermodynamics. (D) it is not possible to convert work entirely into heat. (E) all of these statements are false.

2007-11-21 09:23:24 · 3 answers · asked by Anonymous in Physics

I need to know how many gallons or something of water a normal water pipe can hold.. Its for a science essay =/

2007-11-21 09:22:03 · 4 answers · asked by Anonymous in Engineering

please explain how it's done

2007-11-21 09:21:49 · 3 answers · asked by Anonymous in Physics

Consider the following chart:
Compound Mass Iodine(g) Mass Fluorine(g)
(1) 4.75 3.56
(2) 7.64 3.43
(3) 9.41 9.86
When asked to find the mass of fluorine per gram of iodine in each compound, I found (1) 0.7495g F/g I , (2) 0.44895g F/ g I
(3) 1.0478g F / g I.

I am now asked to explain how these numbers support the atomic theory however, I don't see anyway how they do: they do not support the law of multiple proportions or any other part of the theory - AM I MISTAKEN? if so, how does this support the theory??

2007-11-21 09:20:45 · 3 answers · asked by confusedchemist 1 in Chemistry

The volume of a cube-shaped room is found by the formula A = s3 and if the volume of a room is 1728 ft^3, what is the length of each side?

a 11FT^3
B. 12 ft^3
C. 144 ft^3
D. 576 ft^3

2007-11-21 09:20:39 · 9 answers · asked by lailani l 1 in Mathematics

I did an experiment where I produced copper by combining Fe with CuCl2.2H2O.

I decanted the FeCl and H2O also produced and washed the copper 10 times with water and once with HCl. Then I left it to dry over the weekend.

The percentage yield was 73%.

How would I get an improved percentage yield if I performed this reaction again?

2007-11-21 09:20:36 · 1 answers · asked by ChemHelp 2 in Chemistry