Scientech S9000 - Manual (Page 11)

11
SPECIFIC GRAVITY DETERMINATION
The below balance weighing apparatus shown previously is ideal for determining specific gravity. Specific gravity is the ratio of
the mass of a body to the mass of an equal volume of water. Every mineral has its own specific gravity (SG). A list may be
found in any Handbook of Chemistry and Physics. Specific gravity will classify or authenticate a substance. For instance, a
diamond’s SG is 3.50-3.53 while quartz’s is 2.65.
To determine specific gravity using our balance:
1. Install a below balance weighing hangar as shown in the previous section.
2. Install a below balance weighing apparatus, such as a wire hook, including a pan suspended in a bowl of water. Insure that
the pan and the hanger do not touch any part of the bowl and all are totally submerged. Then tare the balance.
3. Then place the sample to be tested on the balance pan and record the weight reading shown on the display. You may use
any unit of measure you desire.
4. Then place the same sample to be tested on the pan suspended in the bowl of water. Make sure that the sample is
completely submerged in the water and record the weight reading shown on the display.
5. Subtract the reading in Step 4 from the reading in Step 3.
6. Divide the reading in Step 3 by the number calculated in Step 5. The result is the SG of your sample.
EXAMPLE: Reading in Step 3 = 6.50
Reading in Step 4 = 4.25
Subtraction = 2.25
Division (Step 6) = 6.50/2.25= 2.89 specific gravity
DENSITY DETERMINATION
Scientech does not offer a density determination kit nor do you need one to determine density. Density is mass (grams) per unit
volume (cubic centimeters).
In order to determine density of a solid, place a graduated flask with a known volume of water on the pan of the balance, tare the
balance, and then place the solid in the flask of water. Divide the displayed weight in grams by the increased volume of water.
The result is the mass per unit volume of the solid in g/cc.
To determine the density of a liquid, place an empty graduated flask on the balance weighing pan, tare the balance, then pour the
liquid into the graduated flask. Divide the displayed weight in grams by the volume of the liquid. The result is the mass per unit
volume of the liquid in g/cc.
SECURITY BRACKET
A security bracket is provided on the rear panel. If needed, the bracket slides out of the rear of the balance providing a
convenient method of securing the balance.
OPTIONS
The Motorized Internal Calibration Weight (9000-INT), Remote Weighing (7000-04) and Custom Unit of Measure (9000-90)
options must be installed at the factory or by personnel authorized by Scientech. Other options, such as a Scientech PDA and
printers, may be purchased at any time. Please contact Scientech at (303)444-1361 or (800) 525-0522 or email us at
[email protected] for information.
OPTIONAL RS-232 PRINTERS
(Printers must be serial)
There are a few different models to choose from. Please contact Scientech or one of our representatives for more information. A
comprehensive manual is included with each printer when purchased. All printers are set for a 9600 baud rate. To change this
setting please see the printer manual and the RS-232 Front Panel Configuration section. The balance display contents can be
sent to the printer at any time by pressing the balance front panel SEND switch . Balances only communicate with serial
printers.
Many other accessories are available. Please contact Scientech at 303-444-1361 or 800-525-0522 or email us at inst@scientech-
inc.com for more information.