{"id":1106,"date":"2020-06-12T18:41:28","date_gmt":"2020-06-12T16:41:28","guid":{"rendered":"http:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/?p=1106"},"modified":"2020-06-12T18:42:58","modified_gmt":"2020-06-12T16:42:58","slug":"dosage-conductimetrique-du-serum-physiologique","status":"publish","type":"post","link":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/2020\/06\/12\/dosage-conductimetrique-du-serum-physiologique\/","title":{"rendered":"Dosage conductim\u00e9trique du S\u00e9rum Physiologique"},"content":{"rendered":"

Le s\u00e9rum physiologique est une solution tr\u00e8s utilis\u00e9e pour le nettoyage des yeux des b\u00e9b\u00e9s par exemple. Cette solution contient de l\u2019eau et du Chlorure de Sodium NaCl \u00e0 0,9\u00a0%. Ce qui signifie que 100g de s\u00e9rum physiologique contiennent 0,9g de Chlorure de sodium.<\/span><\/p>\n

Nous allons v\u00e9rifier si le s\u00e9rum physiologique que l\u2019on a dans la pharmacie du laboratoire de chimie, est conforme \u00e0 l\u2019\u00e9tiquette.<\/span><\/p>\n

Pour cela on propose de r\u00e9aliser un dosage conductim\u00e9trique par \u00e9talonnage. <\/span><\/p>\n

1\u00a0: pr\u00e9paration de la gamme \u00e9talon\u00a0: <\/b><\/u><\/i><\/span><\/p>\n

On pr\u00e9pare des solutions dans des fioles de 50mL \u00e0 partir d\u2019une solution m\u00e8re de chlorure de sodium \u00e0 1,0.10-2<\/sup> mol.L-1<\/sup><\/span><\/p>\n\n\n\n\n\n\n\n<\/colgroup>\n\n\n\n\n\n
\n

Solution dilu\u00e9e<\/span><\/p>\n<\/td>\n

\n

S1<\/sub><\/span><\/p>\n<\/td>\n

\n

S2<\/sub><\/span><\/p>\n<\/td>\n

\n

S3<\/sub><\/span><\/p>\n<\/td>\n

\n

S4<\/sub><\/span><\/p>\n<\/td>\n

\n

S5<\/sub><\/span><\/p>\n<\/td>\n<\/tr>\n

\n

C (mmol.L-1<\/sup>)<\/span><\/p>\n<\/td>\n

\n

1<\/span><\/p>\n<\/td>\n

\n

3<\/span><\/p>\n<\/td>\n

\n

5<\/span><\/p>\n<\/td>\n

\n

7<\/span><\/p>\n<\/td>\n

\n

9<\/span><\/p>\n<\/td>\n<\/tr>\n

\n

Vs.phy<\/sub> (mL)<\/span><\/p>\n<\/td>\n

<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/tr>\n
\n

Veau<\/sub> (mL)<\/span><\/p>\n<\/td>\n

<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n

2\u00a0: pr\u00e9paration de la solution de s\u00e9rum physiologique\u00a0:<\/b><\/u><\/i><\/span><\/p>\n

Le s\u00e9rum physiologique \u00e0 0.9% (soit 9g.L-1<\/sup>) est \u00e9galement dilu\u00e9e 20 fois. R\u00e9aliser la dilution apr\u00e8s validation du protocole par l\u2019enseignant.<\/span><\/p>\n

3\u00a0: r\u00e9alisation des mesures de conductivit\u00e9<\/b><\/u><\/i><\/span><\/p>\n

\"\"<\/p>\n

L\u00a0a conductivit\u00e9 \u03c3 d\u00e9pend de la nature des ions Xi<\/sub> en solution, de la concentration des ions [Xi<\/sub>] (en mol.m-3<\/sup> ) et de la temp\u00e9rature \u019f.<\/span><\/p>\n

La loi de Kohlrausch indique que la conductivit\u00e9 \u03c3 se calcule par la relation\u00a0:<\/span><\/p>\n

\u03c3=\u03a3\u03bbi<\/sub>[Xi<\/sub>] <\/b><\/span><\/span><\/p>\n

o\u00f9 \u03bb= conductivit\u00e9 molaire des ions en solution (S.m\u00b2.mol-1<\/sup>)<\/span><\/p>\n

\u03bbH30+<\/sub>= 35.10-3\u00a0<\/sup>; \u03bbHO-<\/sub>=19,9.10-3\u00a0<\/sup>; \u03bbNa+<\/sub>= 5,01.10-3\u00a0<\/sup>; \u03bbCl-<\/sub>=7,63.10-3<\/sup><\/span><\/p>\n

Exprimer la loi de Kohlrausch applicable au s\u00e9rum physiologique\u00a0:<\/span><\/span><\/p>\n

A l\u2019aide du conductim\u00e8tre, relever les valeurs de \u03b4 (\u00b5S.cm-1<\/sup>) pour chacune des solutions, puis pour le s\u00e9rum physiologique dilu\u00e9\u00a0:<\/span><\/p>\n\n\n\n\n\n\n\n\n\n<\/colgroup>\n\n\n\n\n
\n

Solution n\u00b0<\/span><\/p>\n<\/td>\n

\n

0<\/span><\/p>\n<\/td>\n

\n

1<\/span><\/p>\n<\/td>\n

\n

2<\/span><\/p>\n<\/td>\n

\n

3<\/span><\/p>\n<\/td>\n

\n

4<\/span><\/p>\n<\/td>\n

\n

5<\/span><\/p>\n<\/td>\n

\n

s.phy<\/span><\/p>\n<\/td>\n<\/tr>\n

\n

C (mmol.L-1<\/sup>)<\/span><\/p>\n<\/td>\n

\n

0<\/span><\/p>\n<\/td>\n

\n

1<\/span><\/p>\n<\/td>\n

\n

3<\/span><\/p>\n<\/td>\n

\n

5<\/span><\/p>\n<\/td>\n

\n

7<\/span><\/p>\n<\/td>\n

\n

9<\/span><\/p>\n<\/td>\n

<\/td>\n<\/tr>\n
\n

\u03b4 (\u00b5S.cm-1<\/sup>)<\/span><\/p>\n<\/td>\n

<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n

4\u00a0: r\u00e9alisation de la courbe d\u2019\u00e9talonnage<\/b><\/u><\/i><\/span><\/p>\n

Avec le logiciel Atelier Scientifique, on trace la droite A=f(C) puis avec le pointeur on se place sur la droite \u00e0 A=<\/span><\/p>\n

Relever la valeur de C correspondante <\/span><\/p>\n

Retrouver, par le calcul, la teneur en Chlorure de Sodium du s\u00e9rum physiologique.<\/span><\/p>\n

Ce r\u00e9sultat est-il conforme \u00e0 l\u2019\u00e9tiquette\u00a0? Calculer l\u2019\u00e9cart relatif=|Cth<\/sub>-Cexp<\/sub>\/Cth<\/sub>| si <5\u00a0% produit conforme.<\/span><\/p>\n

\"\"<\/p>\n

\n

\n

\n

\n

\n

5\u00a0: <\/b><\/u><\/i>Correction et <\/b><\/u><\/i>Calculs :\u00a0<\/b><\/u><\/i><\/span><\/p>\n

\"\"<\/p>\n\n\n\n\n\n\n\n<\/colgroup>\n\n\n\n\n\n
\n

Solution dilu\u00e9e<\/span><\/p>\n<\/td>\n

\n

S1<\/sub><\/span><\/p>\n<\/td>\n

\n

S2<\/sub><\/span><\/p>\n<\/td>\n

\n

S3<\/sub><\/span><\/p>\n<\/td>\n

\n

S4<\/sub><\/span><\/p>\n<\/td>\n

\n

S5<\/sub><\/span><\/p>\n<\/td>\n<\/tr>\n

\n

C (mmol.L-1<\/sup>)<\/span><\/p>\n<\/td>\n

\n

1<\/span><\/p>\n<\/td>\n

\n

3<\/span><\/p>\n<\/td>\n

\n

5<\/span><\/p>\n<\/td>\n

\n

7<\/span><\/p>\n<\/td>\n

\n

9<\/span><\/p>\n<\/td>\n<\/tr>\n

\n

Vs.phy<\/sub> (mL)<\/span><\/p>\n<\/td>\n

\n

5<\/span><\/p>\n<\/td>\n

\n

15<\/span><\/p>\n<\/td>\n

\n

25<\/span><\/p>\n<\/td>\n

\n

35<\/span><\/p>\n<\/td>\n

\n

45<\/span><\/p>\n<\/td>\n<\/tr>\n

\n

Veau<\/sub> (mL)<\/span><\/p>\n<\/td>\n

\n

45<\/span><\/p>\n<\/td>\n

\n

35<\/span><\/p>\n<\/td>\n

\n

25<\/span><\/p>\n<\/td>\n

\n

15<\/span><\/p>\n<\/td>\n

\n

5<\/span><\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n\n\n\n\n\n\n\n\n\n<\/colgroup>\n\n\n\n\n
\n

Solution n\u00b0<\/span><\/p>\n<\/td>\n

\n

0<\/span><\/p>\n<\/td>\n

\n

1<\/span><\/p>\n<\/td>\n

\n

2<\/span><\/p>\n<\/td>\n

\n

3<\/span><\/p>\n<\/td>\n

\n

4<\/span><\/p>\n<\/td>\n

\n

5<\/span><\/p>\n<\/td>\n

\n

s.phy<\/span><\/p>\n<\/td>\n<\/tr>\n

\n

C (mmol.L-1<\/sup>)<\/span><\/p>\n<\/td>\n

\n

0<\/span><\/p>\n<\/td>\n

\n

1<\/span><\/p>\n<\/td>\n

\n

3<\/span><\/p>\n<\/td>\n

\n

5<\/span><\/p>\n<\/td>\n

\n

7<\/span><\/p>\n<\/td>\n

\n

9<\/span><\/p>\n<\/td>\n

\n

A det<\/span><\/p>\n<\/td>\n<\/tr>\n

\n

\u03b4 (\u00b5S.cm-1<\/sup>)<\/span><\/p>\n<\/td>\n

\n

0.2154<\/span><\/p>\n<\/td>\n

\n

0.3007<\/span><\/p>\n<\/td>\n

\n

0.483<\/span><\/p>\n<\/td>\n

\n

0.661<\/span><\/p>\n<\/td>\n

\n

0.834<\/span><\/p>\n<\/td>\n

\n

1.006<\/span><\/p>\n<\/td>\n

\n

0.871<\/span><\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

A= 0.871 et on rel\u00e8ve la concentration de 7.465 mmol.L-1<\/sup><\/span><\/span><\/p>\n

CSphy dilu\u00e9<\/sub>=7.465 mmol.L-1<\/sup><\/span><\/span><\/p>\n

CSphy<\/sub>= 20 x CSphy dilu\u00e9<\/sub>=20 x 7.465 mmol.L-1<\/sup> =149.3=0.1493mol.L-1<\/sup><\/span><\/span><\/p>\n

Cm<\/sub>=C x M=0.1493 x 58.44=8.72 g.L-1 <\/sup>Er<\/sub>=|9-8,72\/9|x100=3,1\u00a0%<5\u00a0% donc conforme<\/span><\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

Le s\u00e9rum physiologique est une solution tr\u00e8s utilis\u00e9e pour le nettoyage des yeux des b\u00e9b\u00e9s par exemple. Cette solution contient de l\u2019eau et du Chlorure de Sodium NaCl \u00e0 0,9\u00a0%. Ce qui signifie que 100g de s\u00e9rum physiologique contiennent 0,9g de Chlorure de sodium. Nous allons v\u00e9rifier si le s\u00e9rum physiologique que l\u2019on a dans … Continuer la lecture de Dosage conductim\u00e9trique du S\u00e9rum Physiologique<\/span> →<\/span><\/a><\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[],"class_list":["post-1106","post","type-post","status-publish","format-standard","hentry","category-tp-et-calculs"],"_links":{"self":[{"href":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/wp-json\/wp\/v2\/posts\/1106","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/wp-json\/wp\/v2\/comments?post=1106"}],"version-history":[{"count":3,"href":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/wp-json\/wp\/v2\/posts\/1106\/revisions"}],"predecessor-version":[{"id":1112,"href":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/wp-json\/wp\/v2\/posts\/1106\/revisions\/1112"}],"wp:attachment":[{"href":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/wp-json\/wp\/v2\/media?parent=1106"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/wp-json\/wp\/v2\/categories?post=1106"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/toulouse-sgencfdt.fr\/WORDPRESS_ITRF\/wp-json\/wp\/v2\/tags?post=1106"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}