|
Books > Social sciences > Education > Teaching of a specific subject
|
Buy Now
A Method of Teaching Chemistry in Schools (Paperback)
Loot Price: R928
Discovery Miles 9 280
|
|
|
A Method of Teaching Chemistry in Schools (Paperback)
Expected to ship within 12 - 19 working days
|
This historic book may have numerous typos and missing text.
Purchasers can download a free scanned copy of the original book
(without typos) from the publisher. Not indexed. Not illustrated.
1906 Excerpt: ... when a known weight of chalk is acted upon by
hydrochloric acid. This experiment is easily done if a small flask
be weighed and about-5 gram of powdered calcium carbonate put in
the flask, which is reweighed. The flask is now fitted with an
indiarubber cork having two holes through which pass a tube bent at
right angles and a drying tube containing calcium chloride
respectively. The rightangled tube must be closed by a piece of
indiarubber tubing fitted with a clamp. The cork is now removed and
two small test-tubes containing concentrated hydrochloric acid are
suspended by means of fine cotton in the flask, the chalk having
been previously covered with distilled water. The cork is then
refitted, care being taken to keep the tubes containing the acid
upright. The whole apparatus is then reweighed, after which the
acid in the test-tubes is upset on the chalk. When all the chalk
has dissolved the clamp is removed from the piece of indiarubber
tubing and air drawn through the apparatus by means of an
aspirator. The clamp is then replaced and the whole apparatus
reweighed. The difference between the second and third weighings
gives the weight of carbonic acid gas given off, and from this the
percentage loss of weight can be calculated. This should be 44 per
cent. The class can next try to find the weight of a litre of
carbonic acid gas. This can be done by fitting up an apparatus
similar to that shown in Fig. 24. The calcium carbonate is placed
in the flask with a little distilled water and the test-tubes are
filled with concentrated hydrochloric acid and suspended in the
flask, which together with the drying tube is then weighed. The
drying tube is then connected to the Winchester, the acid is upset
over the chalk and the clamp connecting the Winchester with t...
General
Is the information for this product incomplete, wrong or inappropriate?
Let us know about it.
Does this product have an incorrect or missing image?
Send us a new image.
Is this product missing categories?
Add more categories.
Review This Product
No reviews yet - be the first to create one!
|
You might also like..
|
Email address subscribed successfully.
A activation email has been sent to you.
Please click the link in that email to activate your subscription.
Welcome to Loot.co.za!
Sign in / Register |Wishlists & Gift Vouchers |Help | Advanced search
(2)
