Here are pictures of 3 instruments from the laboratory pasted onto the notebook page with descriptions: [PASTE OR PRINT PICTURES HERE WITH CAPTIONS] Buret: Used for precise volumetric measurements in titration experiments. Has graduations that allow measurement to within 0.1 mL. Analytical balance: Used to measure small masses with high precision, down to 0.1 mg. Important for quantitative chemical analysis and synthesis. Beaker: Common glassware for mixing, heating, and containing solutions in a variety of volumes. Often used for reaction mixtures and titration procedures.

2. Classifying Chemicals
1. Reagent Grade: Reagent grade chemical
conform to the minimum standards set forth by the
Reagent Chemical committee of the American
Chemical Society (ACS) and are used wherever
possible in analytical work.
2. Primary Standard Grade: Extraordinary purity
is required for a primary standard. Primary standard
reagent is carefully analyzed and the assay is printed
on the container label.
3. Special-Purpose Reagent: chemicals that have
been prepared for a specific application. Included
among these are solvents for spectrophotometry and
high-performance liquid chromatography.

3. 1. Select the best grade of chemical available for
analytical work.
2. Replace the top of every container immediately
after removal of the reagent.
3. Hold the stoppers of reagent bottles between your
fingers.
4. Never return any excess reagent to a bottle.
5. Never insert spatulas, spoons, or knives into a
bottle that contains a solid chemicals.
6. Keep the reagent shelf and the laboratory balance
clean and neat.
7. Observe regulations concerning the disposal of
surplus reagents and solutions.

4.  Use liquid detergent (preferably hot)
 Finish up with distilled water
 Use deionized water (if available)
 For water insoluble solution, use alcohol or
acetone
 Rinsing with reagent – needed especially in
titration
“It is seldom necessary to dry the interior surface of
glassware before use: it can be a waste of time
and potential source of contamination”

5. Marking Laboratory Ware
A chemical analysis is ordinarily performed in
duplicate or triplicate. Each vessel that holds a
sample must be marked so that its content can be
positively identified. Flask, beaker and some
crucibles have small etched areas on which semi
permanent mark can be made with a pencil.
Saturated iron(III) chloride can be used for
markings.

6.  Problem: Overheating
 Bumping cause partial loss of the solution
 Ans: Careful and apply gentle
heating
glass beads minimize bumping

7. An analytical balance is a weighing instrument with a
maximum capacity that ranges from 1 g to a few
kilograms with a precision of at least 1 part in 105
at
maximum capacity.
Macrobalances have a maximum capacity ranging
between 160 and 200 g; measurement can be made
with a standard deviation of ±0.1mg.
Semimicroanalytical balances have a maximum
load of 10 to 30 g with a precision of ±0.01mg.
Microanalytical balance has a capacity of 1 to 3 g
and a precision of ±0.001mg.

10.  Bouyancy error - density of the sample is very
much different from the standard masses.
 Temperature Effect – Failure to allow sufficient
time for a heated object to return to room
temperature.

11.  Top Loading – 150 to 200 g
25,000 g
 Triple Beam balance -

12. Oven drying is the most common way of removing
moisture from solids. This approach is not appropriate
for substances that decompose or for those from which
water is not removed at the temperature of the oven.
Dried material are stored in desiccator while they cool
so as to minimize the uptake of moisture. The base
section of the desiccator contains a chemical drying
agent (desiccants) such as anhydrous calcium chloride,
calcium sulfate, magnesium perchlorate or phosphorus
pentoxide.

14. Weighing by Difference
Weighing by difference is a simple method for
determining a series of sample weights. First the bottle
and its contents are weighed. One sample is then
transferred from the bottle to a container; gentle
tapping of the bottle with its top and slight rotation of
the bottle control over the amount of sample removed.
Following transfer, and its residual contents are
weighed. The mass of the sample is the difference
between the two weighings.

16. Simple Crucibles
Simple crucibles serve only as containers. Porcelain,
aluminum oxide, silica and platinum crucibles maintain
constant mass and are used principally to convert a
precipitate into a suitable weighing form. The solid is first
collected on filter paper. The filter and contents are then
transferred to a weighed crucible, and the paper is ignited.
Filtering Crucibles
Filtering crucibles serve not only as containers but also as
filters. A vacuum is used to hasten the filtration, a tight
seal between crucible and filtering flask is accomplished
with any of the several types of rubber adapters.

17. Sintered-glass Crucibles
Sintered-glass crucibles are manufactured in fine,
medium, and coarse porosities. The upper
temperature limit for sintered glass crucible is
ordinarily about 200o
C. Filtering crucibles made
entirely of quartz can tolerate substantially higher
temperatures.
Filter Paper
Paper is an important filtering medium. Ashless paper
is manufactured from cellulose fibers that have been
treated with hydrochloric and hydrofluoric acids to
remove metallic impurities and silica, ammonia is then
used to neutralize the acids. It is necessary to destroy
the paper by ignition if the precipitate collected on it is
to be weighed.

21. Heating Equipment
Many precipitate can be weighed directly after being
brought to constant mass in a low temperature drying
oven. Such an oven is electrically heated and capable
of maintaining a constant temperature to within 1o
C.
The maximum attainable temperature ranges from
140 to 260o
C, depending on make and model, for
many precipitate 110o
C is a satisfactory drying
temperature.
Microwave laboratory ovens are currently appearing
on the market. Where applicable, these greatly
shorten drying cycles.
Muffle furnace (a heavy duty electric furnace) is
capable of maintaining controlled temperatures of
1100o
C or higher. Long handled tongs and heat
resistance gloves are needed for protection.

22. • Pipets
• Burets
• Volumetric flask
• Measuring cylinder

28. Volumetric glassware is calibrated by measuring
the mass of a liquid (water) of known density and
temperature that is contained in the volumetric
ware.

29. 1. Record all data and observations
2. Supply each entry with a heading
3. Date each page of the notebook
4. Never attempt to erase an incorrect entry, cross it
out with single horizontal line
5. Never remove a page from the notebook
6. Do not overcrowd entries
7. Keep first few pages for table of contents

30.  Take a picture of 3 instruments present in the
laboratory, paste or print directly in the bond paper
with description or usage of the instruments.