Hydrogen
LATEST SYLLABUS
Learning Outcomes:
-
Key
Concepts/ Concerns
of hydrogen
of
describe the preparation
electrolysis
Om water
Introduction
ntroduction to
to tr
terms electrode,
electrolyte,
electrolysis- detailed process not required.
-
hydrogen from.
tom electrolys
of water;
prepare hydrogen
in the lab.
using zinc aand
hydrogond
and uses of
Teparation ot hydrogen in the laboratory
d e s c r i b e properties
reasons).| correlate concepts ot oxtddo a
erenene ot zinc as the metal to be used
[with reasons
e used
lot
Choice ot
of dilute acids
acids
r e m o v a l ot oxygen or
[other than dil. nitric aciaj
Ce
dition and
bosch s process.
Properties & uses of hydrogen.
of hydrogen.
Oxidation & Reduction.
A.INTRODUCTION
Element
Symbol
HYDROGEN
en
Euuction with
removal
3nhad
o
Discovery, occurrenCe
Molecular formula
(
H2
H
Atom of hydrogen
Atomic No.
P
proton
le electron
On=
neutron
of an
equal vol. of a
th as heavy as the average weight
I t is the most abundant element in the universe & constitutes about Uo or the universe
Igitest element
in the universe,
1. DISCOVERY Of hydrogen
Scientist
Robert Boyle
Year
1672
Discover
Established the elementary character of hydrogen
Scientist
Henry Cavendish
Year
1776
Discovery- Stated that hydrogen burnt in air producing water.
Scientist
Year
Antoine Lavoisier
-
Antoine Lavoisier
1783
Discovery-amed the gas hydrogen' meaning water produ
Greek word
- Hyaro = water, gen = prOducer
2. OCCURRENCE-Of hydrogen
IN THE FREE STATE:
occurs in very minute traces in the earth's crust and
and in volcanic gases.
In & around the sun: The interior of the sun consists
mainly of hydrogen
is converted to energy released as heat and
-In
-
traces: Hydrogen
atmosphern
light.
whicn
IN THE COMBINED STATE:
Water: About 1/9th by mass of water is hydrogen.
Acids: Hydrogen forms an important constituent of acids e.g. HCI.
Organic compounas: Organic compounds contain carbon, hydrogen and oxyEen
the main elements. e.g. proteins contain carbon,
hydrogen, oxygen and
Plants & animals: Tissues of plants & animals are made
up of compounds
72
nitrogc
of
hyuu