16—21.
COLLECTION OF GASES
379
connected at D in gure 16—13, the D2 gas may be transferred
with the Toepler pump and stored in the ask (]).
16—21.
Collection of Gases.—Figure 16—13 shows the construct10n 0
a
oe
er
um
use
in t
e co
ect10n o
ases.
e
'prlppd'hll'fg
Th
entire system is evacuated by applying a fore pump at Â. Mercury
is then forced above the cut—off point B by blowing at C. The
A
{_ D
H
J
I
ÊF
_
cms
76'
Fm. 16—13.
Collecting gases
With a Toepler pumpgas is then generated at D. The mercury
reservoir E is then
raised so that the gas
in F and G is cut Off and compressed through
the mercury in the capillary
tube H into the chamber
]
.
E
1â
then lowered, more gas expands into F and the
13 repeat€d
until the approximate pressure
desired is obtamed1n
]
, as measur}g
by the dierence in height of the mercury 1n the U—tube.
y