standard #1 select appropriate lab glassware, balances, time measuring equipment and optical...
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Standard #1
Select appropriate lab glassware, balances, time measuring equipment and optical instruments to conduct an experiment
The SI System The SI system is the metric system. SI stands for System International since it is
used all over the world Length is measured in METERS Weight or mass is measured in GRAMS Volume is measured in LITERS Temperature is measured in Celcius
Length Measurement Length is measured in meters or parts of a
meter 1 meter is a little linger than a yard stick
Weight MeasurementWe weigh things on an balance or scale
Appropriate Measuring Equipment for Science Labs
Volume is the amount of space a
liquid or object takes up Beakers Graduated Cylinders
Flasks
Beakers are better for measuring large amounts of liquid. They do not give a very precise measurement.
Looking at this beaker you can see that it would be hard to measure accurately measure 150 mL because there isn’t a line there.
Graduated Cylinders are good for accurately measuring small amounts of liquid.
You can see that there are
lines for each mL
It is easy to tell 10mL form 30 mL
Flasks are used to measure & stir hot/boiling or dangerous chemicals. The small opening or neck cuts down on splashes that could burn you or damage your skin.
Measuring The Volume of an Object
If you put 40ml of water in a graduated cylinder & then drop a marble in it, the level of the water will go up. The number of mL that the volume goes up is equal to the volume of the marble.
Water line Marble is Water is now at
Is at 40mL put in the 50mL so the cylinder volume of the
marble is 10mL marble
Petri Dishes These are used to grow bacteria. Nutrient AGAR ( jelly like stuff that bacterial grows
in) is put in the bottom of the dish
The red stuff is the This petri dish has bacteria
agar growing in it.
Hand Lens &
Microscopes We use a hand lens (magnifying glass) to see things that are small easier.
Microscopes are used to see & measure things that are too small to see with just your eyes or even with a hand lens
Types of Microscopes
Compound Microscope – uses light to see
through something Good things – you can see living things
you can see things in color
Bad Things you can’t see extremely tiny things
Electron Microscope- uses electron beam
to see something Good things – you can see extremely tiny things
Bad things – the electron beam kills the creature
the image is not in color
Stop Watch
A Stop watch is used to record accurate time in a science experiment just like it is in a track meet.
Which piece of equipment can BEST measure the volume of ink in a pen?
A. 10mL beakerB 10ml graduated cylinderC. 100 mL beakerD. 100mL graduated cylinder
B is correct There is not much ink in an ink pen so you
would need something small to measure it. A graduated cylinder has tiny lines for each
mL. A beaker just has a line for every 10 mL.
Graduated cylinder Beaker
Students are using boiling water in a lab experiment. What type of glass ware would the use?
A. Flask B. pipette C. Graduated cylinder D. Petri Dish
A Flask Because of the shape of a flask
( the skinny neck) the materials inside are less likely to splash out on the students
Which tool can be used to MOST accurately determine the volume of a paper clip?
A graduated cylinderB. beakerC. electronic balanceD. ruler
D graduated cylinder
To determine the VOLUME of the paper clip, you would see how much water it displaced.
Measure the amount of water before the paper clip is added & then again after you put the paper clip in. The difference is the volume of the paper clip.
If you are still confused go back to slide #8
In addition to a watch, what other tool can be used to determine how fast a single-celled organism moves?
A. magnifying glass B. electron microscope C. pipette D. compound microscope
D. Compound microscope This is the only equipment that you could
SEE a one celled organism through that doesn’t kill it.
An electron microscope kills the things that you are looking at so you couldn’t watch it move.
B graduated cylinder
This is the only one that has tiny marks to MOST accurately measure the liquid.
A student wants to grow bacteria on solid nutrient agar. Which type of glassware is MOST appropriate for this procedure?
B is correct Petri dishes are used to grow bacteria & are
filled with nutrient agar ( jelly like stuff) which serves as food for the bacteria