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The Ruler
03-12-2007, 04:52 PM
:sl:

i thought i'd make this thread as i'm hoping that it would help each and every GCSE student that is a member of this forum (and possibly even people who aren't members of this forum).

here, you can post anything that you've learnt today...bearing in min that this is a science and maths thread ONLY...i dont want to see posts regarding the climate or the nazis. this can aso be regarded as a thread where you can ask questions that you do not know the answer to or even quiz each other.

but...as quite a lot of threads, this thread requires you to sign a set of rules.
  • no googling the answer, copying and pasting...feel free to research the topic, make notes...and then come back to answer...that is once you know that you have learnt the topic well.
  • no off-topic posting (duh!)
  • if you are a non GCSE student willing to help us poor enslaved students, feel free to do so.
  • you can only post an answer to a question if you are a GCSE student...but anyone (even if you are not a GCSE student) can ask GCSE science or maths related questions.
*hmm...i think there were more rules...but i've forgotten them...so that's it for now*

this thread can also be used as an excuse as to why you are being online when you are supposed to be revising for your exams...but if the excuse doesn't work, i am not to blame...*i know, i never was a good influence on kids*

first question (as today, i didnt learn anything in school cause i wasnt bothered)...

1. What are the three different types of rocks? Examples for each of the types.
2. Two types of igneous rocks and one example for each type.

:w:
Reply

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strider
03-12-2007, 04:54 PM
I've forgotten all the nitty gritty stuff of GCSE Science,bar biology and some chemistry. :D
Reply

Kittygyal
03-12-2007, 04:58 PM
salmualikum.
i wana ask one please && i need help :D

Q) what is a longitudal wave && also what is a transverse?

Ma'assalama

psst yesh am a blondie :D
Reply

danbilal
03-12-2007, 06:53 PM
they're both two types of waves, sound travels as a longitudinal wave and the same with transverse but it has a higher amplitude and wavelength
Reply

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Kittygyal
03-12-2007, 07:04 PM
salamualikum.
^ are you doing it? or have done it?

okay next question.

Q)how do you find the mass of something && also how do you do the premiter && Area so confusing stuff that is :D

Ma'assalama
Reply

Uthman
03-12-2007, 07:08 PM
Originally Posted by Kittygyal
Q)how do you find the mass of something
Is it Density/Volume?

Originally Posted by Kittygyal
&& also how do you do the premiter
Add up the length of each side?

Originally Posted by Kittygyal
&& Area so confusing stuff that is :D

In a quadrilateral, I think it's length x width

In a triangle it is (Base x Height)/2
Reply

Kittygyal
03-12-2007, 07:11 PM
salamualikum.
am not sure me self on't bother asking me :D

anywho next Quenstion.

Q) how do you do algebra:?
Ma'assalama
Reply

danbilal
03-12-2007, 07:12 PM
yr 11 just competed it
area= base X height
perimeter= total length of all the sides added up together
Reply

danbilal
03-12-2007, 07:13 PM
algebra is too hard 2 explain lol
Reply

Kittygyal
03-12-2007, 07:15 PM
salamualikum.
akay kewl.

now can someone explain the reactivity series of metals?
Ma'assalama
Reply

Kittygyal
03-12-2007, 07:16 PM
Originally Posted by danbilal
algebra is too hard 2 explain lol
salamualikum.
ah akay never mind :D
ma'assalama
Reply

danbilal
03-12-2007, 07:22 PM
all it is that it depends on the metals position in the reactivity series the series is :
sodium
calcium
magnesium
aluminium
zinc
iron
copper
gold
Reply

danbilal
03-12-2007, 07:22 PM
how reactive it is
Reply

Kittygyal
03-12-2007, 07:24 PM
salamualikum.
so which ones are reactive? && which are less ractive?
ma'assalama
Reply

danbilal
03-12-2007, 07:25 PM
top- most reactive
bottom-least reactive
Reply

Kittygyal
03-12-2007, 07:28 PM
salamualikum.
hmmpft forget that qestion you don't understand :lol:

anywho next question.

Q) what do we call the process that plants use to make sugar?

ma'assalama
Reply

danbilal
03-12-2007, 07:34 PM
photosynthesis
Reply

danbilal
03-12-2007, 07:34 PM
r u in yr 11
Reply

Kittygyal
03-12-2007, 07:36 PM
salamualikum.
energy from the sun.......... to the Earth?
Ma'assalama

PSST ERM NEVER DONE :X
Reply

danbilal
03-12-2007, 07:38 PM
u gt msn or anythiung
its photosynthesis
Reply

Kittygyal
03-12-2007, 07:40 PM
salamualikum.
CHOOSE THE CORRECT WORD FROM HERE

energy from the sun.......... to the Earth?

ABSORBED
CONDUCTED
CONVECTED
RADIATED
REFLECTED

i asked another question look above ^
ma'assalama
Reply

danbilal
03-12-2007, 07:43 PM
lol its just 4 work
i dont understand ur question
Reply

Kittygyal
03-12-2007, 08:02 PM
salamualikum.
that will be easier now think so
ma'assalama
Reply

Uthman
03-12-2007, 08:08 PM
:sl:

Radiated?

:w:
Reply

Kittygyal
03-12-2007, 08:10 PM
salamualikum.

Q) the energy is ......... by the dark soil

ABSORBED
CONDUCTED
CONVECTED
RADIATED
REFLECTED

ma'assalama
Reply

Uthman
03-12-2007, 08:18 PM
:sl:

I get the impression that I'm doing your homework for you here, Sister.

posti -
Reply

Kittygyal
03-12-2007, 08:21 PM
salamualikum.
hmpfft where's me nephew lol ''your doing MY homework'' rofl! haha you can say that again && wish :X
m'assalama
Reply

'Abd al-Baari
03-12-2007, 08:44 PM
Sis Kittygal:-
I'm sure i read your a teacher (correct me if i'm wrong and my apoligies if i am)

So if you are shouldn't you be helping us students?

Since no ane answered your question i'll answer
1. What are the three different types of rocks? Examples for each of the types.
2. Two types of igneous rocks and one example for each type.
1.Igneous
2.Metamorphic
3.Sedimentary

Intrusive Igneous (diorite)
Extrusive igneous (basalt)
Just done in school last week!
Reply

The Ruler
03-13-2007, 10:57 AM
Originally Posted by Kittygyal
salamualikum.

Q) the energy is ......... by the dark soil

ABSORBED
CONDUCTED
CONVECTED
RADIATED
REFLECTED

ma'assalama
:sl:

absorbed.

kittygyal is not a student, she's an english teacher. She's only asking the question like one of the rules on my first post says.

next question:

what is it called when...

plants move towards the sunlight?
roots move towards water?
roots move downwards towards gravity?

:w:
Reply

danbilal
03-13-2007, 11:01 AM
1)phototropism
2----
2)geotropism
Reply

cute123
03-13-2007, 11:19 AM
:sl:

I am Asma I would like to help all of you in case of Science and Maths . Qualification wise you can trust me I am an Engineer, giving tutions to IGCSE student. I would love to help you all .

Keep me in your prayers.

:sl:
Reply

danbilal
03-13-2007, 11:20 AM
jazakallah sister
remember me in ur dua's to
Reply

The Ruler
03-13-2007, 05:26 PM
Originally Posted by danbilal
1)phototropism
2----
2)geotropism
correct

and the water one is hydrotropism.

next: how are camels adapted to live in the desert?

:w:
Reply

Kittygyal
03-13-2007, 05:58 PM
walikumassalam.
why is everyone so keen to know my year, my age, my msn :lol: whats next my passport? :X

well i will let you all figure out for ya self if am a student or whats so not hmpfft.

sis Glazier shhhhh :X && people read sis Glaciers rules dudes

i'll let the kiddo's answer inshallah if not then i will answer meself so go on people answer if too late am gonna spill the cat out the bag :)
Ma'assalama
Reply

Uthman
03-13-2007, 06:59 PM
:sl:

Originally Posted by +*Rooh*+
how are camels adapted to live in the desert?

Hmm..

Wide feet with a large surface area so they don't sink in the sand

And their humps are for water storage to prevent dehydration?

:w:
Reply

strider
03-13-2007, 07:15 PM
Originally Posted by Osman
:sl:




Hmm..

Wide feet with a large surface area so they don't sink in the sand

And their humps are for water storage to prevent dehydration?

:w:
Correcto.

Next question: What is the chemical formula for photosynthesis?:)
Reply

Uthman
03-13-2007, 07:49 PM
:sl:

Carbon Dioxide + Water --> Glucose + Oxygen (+ energy)

So it would be 6Co2 + 6H2O --> 6C6H12O6 + 6O2

I learnt that as a balanced formula, hence all the sixes at the front. I don't think I would get the mark for that though because the numbers after the letters are supposed to be small but my computer skills aren't that advanced.

I hope that actually has something to do with the question. Don't wanna look like an idiot. 42 1 -
Reply

danbilal
03-13-2007, 07:51 PM
carbon dioxide+ water - glucose + oxygen
Reply

Kittygyal
03-13-2007, 07:52 PM
salam.
you said it dude^ :D
Ma'assalama
Reply

strider
03-13-2007, 07:53 PM
Originally Posted by Osman
:sl:

Carbon Dioxide + Water --> Glucose + Oxygen (+ energy)

So it would be 6Co2 + 6H2O --> 6C6H12O6 + 6O2

I learnt that as a balanced formula, hence all the sixes at the front. I don't think I would get the mark for that though because the numbers after the letters are supposed to be small but my computer skills aren't that advanced.

I hope that actually has something to do with the question. Don't wanna look like an idiot. 42 1 -
Correcto.:D

Next question: What is the difference between aerobic respiration and anerobic respiration? :)
Reply

danbilal
03-13-2007, 07:55 PM
aerobic- release of energy from the breakdown of glucose
anaerobic- release of a little bit of energy very quickly inside the cells when oxygen is not available
Reply

Kittygyal
03-13-2007, 07:56 PM
salamualikum.
well done dude, now you may ask a question :D
ma'assalama
Reply

hibah786
03-13-2007, 07:57 PM
salam alaikum every1 i jus wanna say that i am new 2 this service n i wanna ask is there sum sort of website specially made for GCSE science coz i am takin ma examz in june n need 2 start revisin specially in chemistry ma salama every1 fi aman allah
Reply

strider
03-13-2007, 07:58 PM
Correct, again.

Next question: Why is the human circulatory system termed as a 'double circulatory system'?
Reply

strider
03-13-2007, 07:59 PM
Originally Posted by hibah786
salam alaikum every1 i jus wanna say that i am new 2 this service n i wanna ask is there sum sort of website specially made for GCSE science coz i am takin ma examz in june n need 2 start revisin specially in chemistry ma salama every1 fi aman allah
Try: www.bbc.co.uk/bitesize

Alternatively, depending on your specific course you can get some truely excellent revision guides to assist you in your revision.
Reply

Kittygyal
03-13-2007, 08:04 PM
salamualikum.
to the ''new'' sis who wnats help go to www.bytesize.com sumet lyk at :D

&& am sure your school sell revision guides get the ''modular'' ones aright
ma'assalama
Reply

The Ruler
03-14-2007, 10:52 AM
Originally Posted by strider
Correct, again.

Next question: Why is the human circulatory system termed as a 'double circulatory system'?
because there is the systematic circulation and the pulmonary circulation

right :?...sytematic is the circualtion that goes heart>artery/aorta>capilaries>Vein/Venacava>heart

pulmonary circulation: pulmonary artery>lungs>pulmonary vein>heart

:confused:

:w:
Reply

mizan_aliashraf
03-14-2007, 11:02 AM
Salam
It's that time again this year. How quickly it has come. May I take this opportunity to wish all our GCSE students the best of luck.
Wassalam
Reply

seeker_of_ilm
03-14-2007, 08:59 PM
Originally Posted by +*Rooh*+
kittygyal is not a student, she's an english teacher.

You gotta be kidding right? English Teacher :rollseyes
Reply

afriend
03-14-2007, 09:03 PM
Originally Posted by seeker_of_ilm
You gotta be kidding right? English Teacher :rollseyes
:giggling: Behave yourself! :p ;D ;D ;D
Reply

aadil77
03-14-2007, 10:00 PM
Here's a chemistry question:

whats the haber process?
What are the optimum conditions for it?
And what is the word equation for it?
nitrogen + hydrogen -----> Ammonia
Reply

strider
03-14-2007, 10:36 PM
Originally Posted by +*Rooh*+
because there is the systematic circulation and the pulmonary circulation

right :?...sytematic is the circualtion that goes heart>artery/aorta>capilaries>Vein/Venacava>heart

pulmonary circulation: pulmonary artery>lungs>pulmonary vein>heart

:confused:

:w:
I was looking for a rather simplified answer along the lines of 'blood enters the heart twice over per complete circuit' but :thumbs_up
Reply

The Ruler
03-15-2007, 09:24 AM
Originally Posted by aadil77
Here's a chemistry question:

whats the haber process?
What are the optimum conditions for it?
And what is the word equation for it?
nitrogen + hydrogen -----> Ammonia
1. haber process is used to make ammonia from hydrogen and nitrogen

2. 250 atmospheric pressure and 450-500C temperature

3. hydrogen + nitrogen (reversible reaction sign thingamajig) ammonia + heat.

next question:

when electrolysing bauxite (aluminium ore), what is used to decrease its melting point?

:w:
Reply

Maarya
03-15-2007, 09:31 AM
Originally Posted by mizan_aliashraf
Salam
It's that time again this year. How quickly it has come. May I take this opportunity to wish all our GCSE students the best of luck.
Wassalam
:sl:
thankyou...insh'allah we will all pass with our brothers and sister's du'as
Reply

E'jaazi
03-15-2007, 09:58 AM
All odd numbers add up to be even and all even numbers add up to be even as well.
Reply

cute123
03-15-2007, 10:14 AM
Originally Posted by E'jaazi
All odd numbers add up to be even and all even numbers add up to be even as well.
:sl:

Hope this formula list helps ,

:w:
Reply

Maarya
03-15-2007, 10:16 AM
Originally Posted by bint abdulhamid
:D saddows is dat all u guyz think bout? REVISING!!!!!!!!!!!!!!!!!!!!!!!!!!11
well, its either revising, getting the grades and being successful, or not revising and getting U's and living the rest of our lives in misery...which would you choose?
Reply

bint abdulhamid
03-15-2007, 10:45 AM
Originally Posted by Maarya
well, its either revising, getting the grades and being successful, or not revising and getting U's and living the rest of our lives in misery...which would you choose?
huh sum ppl go 4 da din instead of dunya
Reply

aadil77
03-15-2007, 09:40 PM
the aluminium is dissolved in cryolite.

Next question:

why is power transmitted at high voltages through power lines?
Reply

'Abd al-Baari
03-16-2007, 08:06 AM
Salams

^Is it because of the large amount of power involved^
Reply

The Ruler
03-16-2007, 09:25 AM
Originally Posted by Abdullah2907
Salams

^Is it because of the large amount of power involved^
nope, but because less energy is lost.

next q:

explain step up and step down transformers.

:w:
Reply

Somalina
03-16-2007, 10:16 AM
Assalama Aleykum

I am doing Gcse Maths
Has anyone done or Is anyone doing the 2D to 3D sequence project
I can't seem to find a formula for the nth term of the pattern when extended to a 3D view

Any help will be appreciated
scusa if the Q doesn't fall under the revision concept:)
May ALLAH swt help us rip the fruits of our hard work (no such thing as good luck and not so good luck) he who fails to plan ,,,,plans to fail:X and nin shaqeesan shaah macabo:D
Reply

S_87
03-16-2007, 10:33 AM
Originally Posted by hibah786
salam alaikum every1 i jus wanna say that i am new 2 this service n i wanna ask is there sum sort of website specially made for GCSE science coz i am takin ma examz in june n need 2 start revisin specially in chemistry ma salama every1 fi aman allah
:sl:

do you want some books? i have i can send them you? they are just a few years old but i didnt really use them and have no idea what to do with them. if you want lemme know :)
Reply

The Ruler
03-16-2007, 08:00 PM
Originally Posted by +*Rooh*+
explain step up and step down transformers.
need help?...why do i see no vounteers?

:w:
Reply

aadil77
03-17-2007, 08:45 AM
transformers use an elcetromagnet to step up or step down voltage and current so that they are suitable for smaller aplliances
Reply

The Ruler
03-17-2007, 04:13 PM
Originally Posted by aadil77
transformers use an elcetromagnet to step up or step down voltage and current so that they are suitable for smaller aplliances
correctos.

next:

what is the value of pi?

(couldn't be bothered to search my brain for a better question).

:w:
Reply

strider
03-17-2007, 04:15 PM
Originally Posted by +*Rooh*+
correctos.

next:

what is the value of pi?

(couldn't be bothered to search my brain for a better question).

:w:
3.142 (The Da Vinci Code drummed it into me).
Reply

The Ruler
03-17-2007, 04:39 PM
Originally Posted by strider
3.142 (The Da Vinci Code drummed it into me).
*cough* the below rule as just been violated...but i guess its okay :)...by the way, you are an AS level student at the moment right sis :?

  • you can only post an answer to a question if you are a GCSE student...but anyone (even if you are not a GCSE student) can ask GCSE science or maths related questions.
so ask away :thumbs_up

:w:
Reply

strider
03-17-2007, 04:44 PM
Originally Posted by +*Rooh*+
*cough* the below rule as just been violated...but i guess its okay :)...by the way, you are an AS level student at the moment right sis :?
Yes, i'm an AS student but retaking GCSE Maths this year. :) So, strictly speaking i haven't broken the rule. :D
Reply

aadil77
03-18-2007, 04:12 PM
Next Question:

What catalyst is used in the production of nitric acid?
Reply

MuHiTH
03-18-2007, 10:27 PM
Salam

I am currently doing GCSE this year, Exams are coming in June :( *PANIC!*

Im getting As for Maths and Low Bs for Science, so if any1 needs any help for Maths gimme a pm.

BTW aadil answer is Ammonia
Wasallam
Reply

The Ruler
03-19-2007, 12:47 PM
next:

ma09025 -

calculate the length of EC.

higher tier.

:w:
Reply

The Ruler
03-20-2007, 05:00 PM
:sl:

hint?

a^2 + b^2 = c^2

[S]
that's pythagoras right
[/S]

:w:
Reply

Kittygyal
03-20-2007, 05:04 PM
salamualikum.
PI huhhhhhhhhh :D :p
ma'assalama
Reply

786rani
03-20-2007, 05:11 PM
Originally Posted by +*Rooh*+
:sl:

hint?

a^2 + b^2 = c^2

[S]
that's pythagoras right
[/S]

:w:
pythagoras is easyyyyyyyyyyyy
rani
Reply

The Ruler
03-21-2007, 04:54 PM
:sl:

its been 2 days...you have a further one day...if not solved, i'll do it.

:w:
Reply

Kittygyal
03-21-2007, 04:55 PM
salam.
sis solve what?
ma'assalama
Reply

aadil77
03-21-2007, 07:16 PM
sorry Rooh the catalyst is not 'iron oxide' that is used in making ammonia, the catalyst used in making nitric acid is platinum
Reply

aadil77
03-21-2007, 07:31 PM
the length is 6.16cm or root38

Maths questions are difficult to type so i'll stick to science

Next question:

what are the three types of radiation?
And which one of them penetrates the most.
Reply

MuHiTH
03-21-2007, 07:39 PM
Question is soo easy

the radiation types are Alpha, Beta and Gamma

Gamma penetrates the most
Reply

The Ruler
03-22-2007, 01:04 PM
Originally Posted by aadil77
sorry Rooh the catalyst is not 'iron oxide' that is used in making ammonia, the catalyst used in making nitric acid is platinum
okay :confused: so what is the catalyst used to make ammonia :?...

:w:
Reply

aadil77
03-22-2007, 09:35 PM
the catalyst for makin ammonia is iron
Reply

Al-Hanbali
03-23-2007, 06:18 PM
:sl:

a fairly simple one:

What is the group of elements with full outer shells called?
Reply

The Ruler
03-23-2007, 06:29 PM
Originally Posted by Dhul-Fiqhar
What is the group of elements with full outer shells called?
they are called the noble gases. they are in grou 8 and are unreactive.

wat are the group 7 gases called...name all of them (without refering them to a periodic table)...also, give electronic onfiguration of each.

:w:
Reply

Al-Hanbali
03-23-2007, 06:57 PM
:sl:

Group 7 elements are called "Halogens"

They are:
  • Flourine

  • Chlorine

  • Bromine

  • Iodine

  • Astatine


dont know the configurations of each.....
Reply

hibah786
03-23-2007, 06:58 PM
Umm Brothers And Sisters How Do We Work Out:
A. The Volume Of A Cylinder
B. The Surface Area Of A Cylinder
Shukran Ahktee Wa Akhee
Reply

hibah786
03-23-2007, 06:59 PM
And Another Problem I Have:
I Have No Idea On How To Balance Equations In Chesmitry Plz Help Shukran
Reply

aadil77
03-23-2007, 07:34 PM
volume is (pii x radius^2 x length) sorry difficult to type maths symbols
Reply

The Ruler
03-23-2007, 08:02 PM
Originally Posted by hibah786
B. The Surface Area Of A Cylinder
a cylinder has two circles...ie the two surfaces...and the tubical (?) surface...to find the surface area of the two circles, use the normal circle area formula ie...area= pi x radius^2
timesthe answer by two to find out the surface area of both the circles.

to find the surfac area of the cylinder body, find te circumference of the circle which is...2 x pi x radius...times the answer with the lenth to find out the surfce area of the cylinder body (aka the 'tubical' surface).

and this answer with that of the 2 circles calculated in the first part...and you should get the answer.

I Have No Idea On How To Balance Equations In Chesmitry Plz Help
to understand that, you must first understand how to calculate the number of atoms in a compound.

to begin, tell me the number of oxygen mlecules and the number of hydrogen molecules in the water fomula

^that question is for sis hibah786 only.

:w:
Reply

Al-Hanbali
03-24-2007, 01:55 PM
:sl:

What is an "Ion"?
Reply

A7med
03-24-2007, 01:58 PM
^ its an "on" with an "I" at the beginning
Reply

The Ruler
03-24-2007, 02:05 PM
Originally Posted by A7med
^ its an "on" with an "I" at the beginning
funny.

What is an "Ion"?
when an atom loses its electron or gains an electron to an element, it becomes charged and beoms an ion.

is that right?...i know what an ion is but explaining what it is is kinda hard.

next question:

explain ionic bonding and give an example of one.

:w:
Reply

afriend
03-24-2007, 03:46 PM
:sl:

Ionic bonding is when two atoms bond together by losing/gaining an atom, groups in the periodic table should also be put into consideration when the Ionic bonding is concerned.

The groups are to show the outer most electrons in the final shell of an atom, for example, Na (sodium) is in group 1, and hence has 1 electron in the outer shell. Sodium has 11 electrons, in order for an atom to be stable, the electrons in the shells must satisfy this ordering: 2(first shell):8(second shell):8(third shell):18....and so on, in this case it will have 2:8:1.

So now, in order to become stable it must react with an element from group 7 to satisfy 8 electrons in the outer shell. However, because there is only 1 atom, it is easier to give away that one electron to the other element in group 7 in which the G7 element satisfies the 8 in the outer shell pattern.

Electrons are negatively charged, and protons (in the nucleus) are positively charged, and because the negatively charged electron has been lost there are 8 protons (+ charged) so the Na atom now becomes a positively charged atom.

:D

:w:
Reply

Al-Hanbali
03-24-2007, 07:51 PM
:sl:

Explain what "emulsification" is?
Reply

afriend
03-24-2007, 10:24 PM
:sl:

Now that.....I do not have an explanation to ;D

:w:

PS. Eager to find out though....bring on the jargon :D
Reply

The Ruler
03-25-2007, 12:30 PM
Originally Posted by Dhul-Fiqhar
Explain what "emulsification" is?
for double science, we dont really need to know much about this topic except the example about oil and water. because they cannot be mixed together, they are immiscible. they can only be mixed for a short while when you shake them up. this type of mixture is called an emulsion. in salad cream, the egg yolk is known as the emulsifying agent. food (such as chocolate) contain E numbers which are emulsifying agents.

whilst revising this topic, i had a look at the triple science bit, and found out about colloids. a colloid is a finely dispersed mixture of two or more substances that do not dissolve into each other.

next:
  • Multiply out and simplify the following:
    (3x - 1)(2x + 5)
  • 2mr2 + lmr
  • x2 + 9x + 18
have fun.

:w:
Reply

aadil77
03-26-2007, 09:40 PM
1. 6x^2 + 13x - 5, x= 1/3 and x= -3/2

2. rm(2r + l)

3. (x+3)(x+6), so x= -3 and x= -6
Reply

...
03-27-2007, 05:12 PM
emulsification is the break down of fats into smaller droplets (e.g due to bile)
Reply

strider
03-28-2007, 02:31 PM
Originally Posted by Rose_Ice
emulsification is the break down of fats into smaller droplets (e.g due to bile)
Correcto.

Bonus question: Where does the emulsification of fats occur in the human body?:D
Reply

786rani
03-28-2007, 07:15 PM
is it the bile duct when food is passing through the duodenum
rani
Reply

Al-Hanbali
04-02-2007, 06:16 PM
:salamext:

Quadratics

Solve the equation:

(3x+2)(2x-1)=3
Reply

The Ruler
04-02-2007, 06:32 PM
:sl:

i dont know what quadratics mean...so i just went with what i thought was right; thus:

6x^2 - 3x + 4x - 2 = 3
6x^2 + x -2 -3
6x^2 + x -5

probably wrong but hey...now that its done, i aint bothered to erase it.

:w:
Reply

AhlaamBella
04-02-2007, 06:34 PM
please can someone provide a simple explanation to Eutrophication? It knocks me for 6 everytime. :S :S :S
Reply

The Ruler
04-02-2007, 06:36 PM
Originally Posted by DeepOcean
please can someone provide a simple explanation to Eutrophication? It knocks me for 6 everytime. :S :S :S
recalling from memory, isnt it when nitrates (or whatever) are washed from land into the rivers/water causing the plants to die?

:w:
Reply

AhlaamBella
04-02-2007, 06:37 PM
yeah something like that. My teacher was going on about the 'six steps' I was completely lost lol
Reply

Al-Hanbali
04-02-2007, 07:17 PM
:salamext:

Originally Posted by +*Rooh*+
:sl:

i dont know what quadratics mean...so i just went with what i thought was right; thus:

6x^2 - 3x + 4x - 2 = 3
6x^2 + x -2 -3
6x^2 + x -5

:w:
So far correct....

then if you factorize: (6x - 5)(x + 1)= 0

either: (6x - 5)=0 or (x + 1)= 0

so: 6x = 5 or x = -1

therefore the two solutions are: x = 5/6 or -1

dont know if i explained properly but thats that
Reply

Al-Hanbali
04-04-2007, 01:01 PM
:salamext:

What are the uses of the following noble gases?

Helium

Neon

Argon

Krypton
Reply

786rani
04-04-2007, 04:15 PM
He helium The gas is much less dense than air (lighter) and is used in balloons and 'airships'. Because of its inertness it doesn't burn in air UNLIKE hydrogen which used to be used in large balloons with 'flammable' consequences e.g. like the R101 airship disaster! Helium is also used in gas mixtures for deep-sea divers.

Ne neon just like this website! Neon gives out light when high voltage electricity is passed through it, so its used in glowing 'neon' advertising signs and fluorescent lights.

Ar argon Argon, like all the Noble Gases is chemically inert. It used in filament bulbs because the metal filament will not burn in Argon and it reduces evaporation of the metal filament. It is also used to produce an inert atmosphere in high temperature metallurgical processes, eg in welding where it reduces brittle oxide formation reducing the weld quality. Its bubbles are used to stir mixtures in steel production. Argon is the cheapest to produce.

Kr krypton Not used by superman! BUT is used in fluorescent bulbs, flash bulbs and laser beams.
Reply

Al-Hanbali
04-06-2007, 11:37 AM
:salamext:

Masha'ALLAH...

next?
Reply

AhlaamBella
04-06-2007, 11:55 AM
Polymerisation? All that alkanes and alkenes stuff! :S
Reply

The Ruler
04-06-2007, 12:17 PM
:sl:

Originally Posted by DeepOcean
Polymerisation? All that alkanes and alkenes stuff! :S
ok...bear with me cause i really have hard time explaining since its all recalling from memory.

ok so...alkanes are saturated and alkenes are unsaturated...to be honest, i dont really now what each of that means but i only know that. they are both from the family of hydrocarons. the first 4 alkanes are methane CH4, ethane C2H6, propane C3H8 and butane C5H12. the formula to find the H for alkanes is CnH(2n+2)...now onto the alkenes. alkenes are usually carbon carbon double bond. and the stuff is usually spelt with an 'e' where the 'a' is. eg. instead of ethane, it is ethene. the formula to find the H in alkenes is CnH(2n). eg. ethene C2H4 and propene C3H6. the test for alkenes and alkanes is the bromine water thingamajig. alkenes turn bromine water (a brown colour solution :?) colourless.

polymerisation...
there are monomers and polymers...you ought to know the difference between the two. a monomer is a simple molecule eg. C2H4...a polymer is a large molecules formed from simple smal molecules...i dont have an example...cause i cant remember one ^o)
and i think...if i remember correctly...only alkenes can polymerise this is because of their double bond. polymerisation is when lots of small molecules join together end to end to form a large one. these are called addtion polymers. eg. ethene...lots of ethene = poly ethene, propene...lots of propene = polypropene.

i did a google search nd found a perfect image explaining what i just said above:

polyethene -

the 'part of a polyethene molecule' can also be drawn like this:

thumb Polyethene monomer -

:w:
Reply

AhlaamBella
04-06-2007, 12:30 PM
JazakAllah Kheir sis :thumbs_up :thumbs_up :)
Reply

The Ruler
04-12-2007, 03:44 PM
Originally Posted by DeepOcean
JazakAllah Kheir sis :thumbs_up :thumbs_up :)
its alright :)

next...its science higher tier...

how is insulin produced?...

:w:
Reply

786rani
04-12-2007, 04:45 PM
Insulin is a hormone that regulates the amount of glucose (sugar) in the blood and is required for the body to function normally. Insulin is produced by cells in the pancreas, called the islets of Langerhans. These cells continuously release a small amount of insulin into the body, but they release surges of the hormone in response to a rise in the blood glucose level.

my 10 yr old sister has diabetes she should know.
rani
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