Hydrogen

?
Boiling point
20K
1 of 17
Melting point
14K
2 of 17
Density
0.08g dm-3
3 of 17
H-H bond length
0.74 angstrums
4 of 17
Bond energy
436kJ mol-1 (generally unreactive at RT)
5 of 17
Electronegativity
2.2
6 of 17
Synthesis of H2
Steam reforming (notes for eqtns) produces most of 40 mill. tonnes p.a.
7 of 17
Uses of H2
Haber Bosch (produce ammonia). Conversion of syn-gas to methanol. Also hydrogenation of alkenes and reduction of metals
8 of 17
Group 1 hydrides
React rapidly with H2O. 2MH+H2O -> 2MOH+H2. Laregly ionic, colourless. LiH = largest covalent character
9 of 17
Group 2 hydrides
Largely ionic, colourless. MgH2 largely covalent character. BeH2 different - covalent polymeric (3c-2e). React with H20 but BeH2 relatively stable.
10 of 17
Diborane
Made from BF3 and NaH. Gas. Flammable in air -> B(OH)3. 3c-2e bonds. Strong lewis acid
11 of 17
Group 14 hydrides
Many CnHm. Si, Ge, Sn = gasses + decompose on heating. Combust to EO2 + H2O. Formed from ECl4 + LiAlH4. Act as H+ source with strong base
12 of 17
Group 15 hydrides
Gas. Free e- pair = lewis bases. Also H+ source for strong bases. Both for ammonia- 2NH3 ->NH4+ + NH2-. Made same way as 14 (except ammonia)
13 of 17
Group 16 hydrides
toxic gas (except h2o). Lewis bases. Lewis acids in h2o.
14 of 17
H2O2
Strong oxident. 2 mill. tonnes produced p.a. Bleaching, anti-septics. Thermodynamically unstable.
15 of 17
Group 17 hydrides
gas. acidic.
16 of 17
What are guest molecules in the holes of ice called?
Clathrate hydrates
17 of 17

Other cards in this set

Card 2

Front

14K

Back

Melting point

Card 3

Front

0.08g dm-3

Back

Preview of the back of card 3

Card 4

Front

0.74 angstrums

Back

Preview of the back of card 4

Card 5

Front

436kJ mol-1 (generally unreactive at RT)

Back

Preview of the back of card 5
View more cards

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Inorganic resources »