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.

Which tool should be used to MOST accurately measure 22.0 mL of liquid?

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

Which graduated cylinder should be used to MOST precisely determine the volume of a marble?

B. This is because Cylinder B is the only one

that has a mark or line for EACH ML