Tutorial

1. Density can be defined as mass per unit volume and it which relying on temperature and

pressure for gaseous material while and as for liquid, it is highly dependent on temperature

than pressure. The S.I Units used for density is kg/m³.

2. Other units for density are g/cm³ and Ibm/ft³

3. Specific gravity of a liquid can be defined as the ration of density of a substance to the density

of some standard substance at a specified temperature (Water at 4°C; normal temperature for

which ρH2O is 1000 kg/m3 )

4. Density of liquid is not constant because density of liquid will be affected by change in

temperature and pressure.

5. In a normal hydrometer, there is a calibrated glass tube ending in a weighted glass sphere that

makes the tube stand upright when placed in a liquid. The lower the density of the liquid, the

deeper the tube sinks.

6. Hydrostatic pressure is directly proportional to density. Therefore as density increases the

pressure increases as well

7. Hydrometer

8. Besides the method shown, the other method is by using density bottle method, where it

requires to fill the bottle with an unknown liquid and separately with water and measuring the

respective masses can be used, with constant temperature.

9. The calibration of pressure transmitter is necessary to the old power plant might reduce its

efficiency.

10. Errors that had been identified are parallax and technical errors. Hydrometer showed

inaccurate reading so the exact reading could not be reliable. This may due to the refraction

in the tube of hydrometer. Meanwhile, technical errors lied on the material plant that was

used for the experiment might be a material that had been used for a long period so the

accurate value of density as well could not be exactly identified.

References

1. Experiment Manual DMC 200. QDR Marketing SDN BHD

2. Industrial Pressure, Level, and Density Measurement, Donald R. Gillum, ISA 2009,

3. Instrumentation for Process Measurement and Control, Third Edition, Norman A.

Anderson, CRC Press, 22 Oct 1997

4. Instrument Engineers' Handbook, Fourth Edition, Volume One: Process Measurement and

Analysis, Bela G. Liptak, CRC Press, 27 Jun 2003

Conclusions and Recommendations

The objective of this experiment was achieved. The following parameters were

compared. The type of tank which is open tank and closed tank shows difference is density as

well as specific gravity measurement. Besides that, the condition of the water heater whether its’

on or off also shows significant change in the results obtained. The highest density and highest

calculated specific gravity can be observed in closed tank with the heater on whereas the lowest

deviation with hydrometer is achieved in open tank with heater off.

There were several problems that were identified in the experiment. The first, is the level

of overflow which was difficult to observe. Besides that, the position of certain valve out of

reach causes error while adjusting. The level of pressure entering is also difficult to monitor. All

this valves as well as measuring tool should be placed within reach to aid the experiment to be

conducted. Take reading of the meter at least three times to avoid reading error and to make sure

the reading is precise an accurate.