Physics, Chemistry and Biology: Post your doubts here!

[hredoymohammad]

how does radiation ionize air into positive and negative ions

 

[Deevans]

I NEED THE MARK SCHEME TO BIOLOGY PAPER 1 MAY/JUNE 2002 0590/01!!! PLEASE ANYONE KIND ENOUGH? THANKSS!!

 

[Deevans]

Please? anyone with the Mark Scheme to biology paper 1 may/June 2002 0590! Would really appreciate it! Need it asap. xo

 

[absolute100%]

IGSE Physics w11 papers please. Desperately need em please asap
thanx in adv.

 

[Spirit95]

how does radiation ionize air into positive and negative ions

Ionization is always about knocking-off electrons from an atom. Therefore, an alpha particle for example, which is the most ionizing, would knock-off electrons from air molecules, causing them to become anions. These electrons that are knocked-off are absorbed or attracted by other atoms, making them cations.

 

[KZW]

Please? anyone with the Mark Scheme to biology paper 1 may/June 2002 0590! Would really appreciate it! Need it asap. xo

There is no 0590 in IGCSE. I think you are referring to O levels 5090, which is sat in SE asia.

Now, I can't find the marking scheme but it seems that you're not the only one.

http://www.xtremepapers.com/community/threads/5090-1-may-june-2002-biology.4712/

All his answers seem to be right, so just follow that Hope this helps.

 

[sweetiepie]

http://www.xtremepapers.com/community/threads/useful-stuff-compiled.10273/ for notes

 

[JOEJOE]

O/N 2003 P6, 0625, Q1D, help me out!

 

[waleed82]

http://www.xtremepapers.com/CIE/Cambridge IGCSE/0625 - Physics/0625_s02_qp_6.pdf

hey guyz in da link about can anyone of ya plz help me with the question 4...............plz solve / explain it....................................

 

[ktc]

O/N 2003 P6, 0625, Q1D, help me out!

Q.1 d)

(i) To find the estimated volume, it is the area of the shaded part x c

[0.7 x 0.6 x 0.5] x 5.3

= 1.113 cm3

(ii) The actual external volume is the volume we calculated in part (c ) – the volume in part (d ) (i)

32.41 – 1.113 cm3

= 31.3 cm3

[This answer is an estimation, and therefore, you’re answer might not suite mine, but as long as it is within the range given in the marking scheme, you’re good to go]

The range for answer (d) (i) is 0.5 – 2 cm3

 

[Iridescent]

Q.1 d)

(i) To find the estimated volume, it is the area of the shaded part x c

[0.7 x 0.6 x 0.5] x 5.3

= 1.113 cm3

(ii) The actual external volume is the volume we calculated in part (c ) – the volume in part (d ) (i)

32.41 – 1.113 cm3

= 31.3 cm3

[This answer is an estimation, and therefore, you’re answer might not suite mine, but as long as it is within the range given in the marking scheme, you’re good to go]

The range for answer (d) (i) is 0.5 – 2 cm3

Why do we subtract the area? Shouldn't it be the volume which should subtracted from the actual volume?

 

[ktc]

Why do we subtract the area? Shouldn't it be the volume which should subtracted from the actual volume?

Look at my post again, that’s precisely what I did

 

[Iridescent]

Look at my post again, that’s precisely what I did

Sorry i didn't see that.

 

[waleed82]

Q.1 d)

(i) To find the estimated volume, it is the area of the shaded part x c

[0.7 x 0.6 x 0.5] x 5.3

= 1.113 cm3

(ii) The actual external volume is the volume we calculated in part (c ) – the volume in part (d ) (i)

32.41 – 1.113 cm3

= 31.3 cm3

[This answer is an estimation, and therefore, you’re answer might not suite mine, but as long as it is within the range given in the marking scheme, you’re good to go]

The range for answer (d) (i) is 0.5 – 2 cm3

hey can u help me with my question i.e can u solve it too for me.........

 

[ktc]

hey can u help me with my question i.e can u solve it too for me.........

A really good friend of mine already had the marking scheme for this year, luckily, and gave it to me. So here’s the answer to your question.

 

[waleed82]

A really good friend of mine already had the marking scheme for this year, luckily, and gave it to me. So here’s the answer to your question.

so can u send it to me?????????

 

[ktc]

so can u send it to me?????????

I don’t think that necessary

 

[waleed82]

y??????????

 

[Vogue]

http://www.xtremepapers.com/CIE/Cambridge O Levels/5070 - Chemistry/5070_w10_qp_42.pdf

Question 10 part b .........help please!
they say that for experiment 2, we got to draw two intersecting straight lines.....how is that possible?

 

[ktc]

y??????????

Oh, I just realized you couldn’t view the [picture] answer in my previous post!

Can you now?