Presentation from history, structure and forms of use of the analytical (scale) balance in laboratories of the chemistry.

1. ANALYTICAL BALANCE (OR SCALE)
TEACHER GRADUATION QUEMISTRY (1 SEMESTER)
PRATICAL QUEMISTRY I CLASS
CHIAKI
DANDARA
ELIOMAR
ENZO

2.  ORIGINAL NAME'S BISLINX (of Latin bis = two e linx = dishe);
 ORIGIN OF OLD EGYPT;
 KEPT TWO DISHES CARACTERISTIC DURING 40 CENTURIES.
STORY OF THE BALANCE (OR SCALE)
http://www.balancas-analiticas.com.br/home/balanca-historia/

3. BALANÇA ANALÍTICA: COMO SURGIU
 ADVENT OF THE IATROCHEMISTRY
(medical chemistry old);
 IT WAS NECESSARY FOR USE OF
POISONOUS SUBSTANCES;
 WAS NECESSARY FOR THE LARGE
PRECISION OF THE RESULTS.
http://www.balancas-analiticas.com.br/home/balanca-historia/

4. ANALYTICAL BALANCE(SCALE): STRUCTURE
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422004000600030
Reading in the figure 11: Scheme basic of
the balance from one dish: A: command
lock/unlock; B: break damper of dish
(works when the balance is locked); C:
dish of the balance; D: weight; E: cleaver
of the ensemble of weight and also of the
dish; F: transom; G: central cleaver; H:
counterweight; I: optical scale graduated.

5. ELETRONIC BALANCE(SCALE): STRUCTURE
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422004000600030
Reading in the figure 12: principle basic
of the electronic balance: A: dish; B:
internal weight for calibration; C:
current; D: processor (responsible for the
controlling calibration, tare and on/off);
E: digital display of the mass; F: sensor;
G: bobin.

6.  TO TO DETERMINE THE MASS OF THE
SUBSTANCE, IN SOME CHEMISTRY
ANALYSIS;
 ABSOLUTE OR RELATIVE QUANTITY
OF ONE OR OF OTHERS
CONSTITUENTS OF THE SAMPLE.
ELETRONIC BALANCE(SCALE): USE

7.  GET ACCURACY OF DATA;
 TO SIDE, IT WE HAVE AN
EXAMPLE OF YOUR USE
WITH AN EMPTY PORCELAIN
DISH.
30.547
30.5477
30.5484
30.5491
30.5498
30.5505
30.5512
30.5519
30.5526
0 2 4 6 8 10 12
Valueofthemass(g)
Number of weighings
Variation of the porcelan empty dish mass
ELETRONIC BALANCE(SCALE): USE PRATICE

8. PRESENTATION REFERENCES
 http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422004000600030 (PORTUGUESE)
 http://www.balancas-analiticas.com.br/home/balanca-historia/ (PORTUGUESE)
 https://history.nih.gov/exhibits/balances/ (ENGLISH)