OCR Chemistry F321 Exam. - [Next Tuesday[

OP

What is the bond angle in H2O2?

its either 180 or 104.5?

Reply 41

Original post by otrivine

good question let me see could it be 104.5 ? it has to either 104.5 or 180 ?

i read online but its defo not bent or linear they'r all sayin its 109* wtf is 109... lool pyramidal is 107 but thing is theres like 2 lone pairs on each oxygen :s

Reply 42

Original post by TheFootyKing19

What is the bond angle in H2O2?

its either 180 or 104.5?

did u copy my answer?lool

Reply 43

Original post by Craming Revision

i read online but its defo not bent or linear they'r all sayin its 109* wtf is 109... lool pyramidal is 107 but thing is theres like 2 lone pairs on each oxygen :s

thats shocking how did they find out what is the structure like?i am sure there is a double bond between the oxygens ?

Reply 44

Original post by otrivine

thats shocking how did they find out what is the structure like?i am sure there is a double bond between the oxygens ?

if there were a double bond between the oxygens then there wouldnt be an electron for hydrogen to be bonded to as theres 2 pairs of electrons on each side of the oxygen even with the double oxygen bond

Reply 45

Original post by Craming Revision

if there were a double bond between the oxygens then there wouldnt be an electron for hydrogen to be bonded to as theres 2 pairs of electrons on each side of the oxygen even with the double oxygen bond

but 4 electrons sharing right with 2 oxygen and 2 electrons between oxygen and hydrogen and another 2 electrons between oxygen and hydrogen so makes it 8 electrons and full outer shell that why i thought its linear? but how can you tackle these types of question?

Reply 46

Original post by otrivine

but 4 electrons sharing right with 2 oxygen and 2 electrons between oxygen and hydrogen and another 2 electrons between oxygen and hydrogen so makes it 8 electrons and full outer shell that why i thought its linear? but how can you tackle these types of question?

seriously no clue lmao im predicted an a in chem in both unit 1 and 2 i dont get the bonding in h202 but thing is in jan 2012 paper i got the nh2h bonding right i cant seem to put my finger on h2o2... its cause nitrogen in nh2h is in group 3 so its -3 so it was easier to find out however o2 is in group 2 so it needs to gain 2 electrons and h needs to gain 1 electron x2 h x o = 2h 4o spare electrons. mhm so i rekon it would be a double electron in the middle of the bond. :3 still clueless lol it was in a paper in jan 2007 btw

Reply 47

Happy revision everybody!

Here's some:

what are the ionic side equations for the reaction of Mg with water.

how many full orbitals are there in aluminium (1s2 2s2 2p6 3s2 3p1) - think about it

define disproportionation
define a mole
define electronegativity

Reply 48

JuxtaposedJames

1

Has anyone got the jan 2012 paper?

Reply 49

Original post by Pride

Happy revision everybody!

Here's some:

what are the ionic side equations for the reaction of Mg with water.

how many full orbitals are there in aluminium (1s2 2s2 2p6 3s2 3p1) - think about it

define disproportionation
define a mole
define electronegativity

how many orbitals? :3

Reply 50

Original post by Pride

Happy revision everybody!

Here's some:

what are the ionic side equations for the reaction of Mg with water.

how many full orbitals are there in aluminium (1s2 2s2 2p6 3s2 3p1) - think about it

define disproportionation
define a mole
define electronegativity

1) do you want an equation with mg and water? or ionic you want
2) is it 6?
3) a redox reaction where an atom gets both oxidised and reduced
4)Amount of substance contating many particles as there are carbon atoms in exactly 12 of carbon-12 atom#
5) the measure of an atom to attract both of the electrons in a covalent bond

Reply 51

Original post by Craming Revision

how many orbitals? :3

so what should i do for h2o2 if it comes up and what is the name pyramidal oh getting scared :redface:

Reply 52

OP

Disproportionation - in which a chemical reaction where an element has been simultaneously reduced and oxidised.

Mole - the amount of any substance containing as many particles as their are exactly carbons atoms in 12g of the carbon-12 isotope.

Electronegativity - as the ability of an atom to attract the shaired pair of electrons in a covalent bond

Reply 53

Original post by otrivine

so what should i do for h2o2 if it comes up and what is the name pyramidal oh getting scared :redface:

It won't come up...

Reply 54

OP

I personally think the definition of RAM, Calculating RAM, Calculating Empirical Formula, drawing covalent and ionic structures and hydrogen bonding, defining salt, calculating moles/conc/volume, Redox reactions is a MUST on tomorrows paper :wink:

Reply 55

OP

Original post by otrivine

so what should i do for h2o2 if it comes up and what is the name pyramidal oh getting scared :redface:

It's not on the syllabus - if a weird one does pop up then you can say electron pairs repel, lone pairs repel more and you will get 2 marks out of a possible 3/4 :smile:

Reply 56

Original post by otrivine

1) do you want an equation with mg and water? or ionic you want
2) is it 6?
3) a redox reaction where an atom gets both oxidised and reduced
4)Amount of substance contating many particles as there are carbon atoms in exactly 12 of carbon-12 atom#
5) the measure of an atom to attract both of the electrons in a covalent bond

1) yeah, so Mg is oxidised, the equation for that. Then H2O is reduced, the equation for that. Doing the full equation helps.

2)correct.
3)say the same element is both ox and red, not the atom
4 and 5)sounds good.

Reply 57

Original post by Pride

1) yeah, so Mg is oxidised, the equation for that. Then H2O is reduced, the equation for that. Doing the full equation helps.

2)correct.
3)say the same element is both ox and red, not the atom
4 and 5)sounds good.

how did you get that it is 6 full orbitals?

Reply 58

JuxtaposedJames

1

Original post by clownfish

It's on here: http://www.thestudentroom.co.uk/misc.php?do=showattachments&t=1943168

Cheers

Reply 59