LAB: Chemical reactions – a bag of change

PREFACE:

In this lab activity, you will mix 3 unknown substances together in a bag and observe the changes that occur.  There will be both chemical changes and physical changes. Observation skills are crucial for this lab investigation.   Watch for changes in state (solid, liquid, gas), colour (use noun-colour description), volume (mL), temperature, and anything else you can detect.   Do not smell any of this substances please.

 

MATERIALS:   PLEASE NOTE WHMIS LABELS AND ACCORDING SAFETY

Chemical A (a white solid) Chemical B (a white solid)

Chemical C (a blue liquid) 50 mL graduated cylinders

Plastic bag goggles

 

PROCEDURES:    

GOGGLES ARE DONNED 

& NOT REMOVED UNTIL EVERYONE’S LAB CONCLUSION!!!!

2. Add one spoonful of Chemical A (sodium bicarbonate) on the left side of the zip-lock bag.  Describe and record the properties for Chemical A.  

 

 

 

What is it’s formula?

 

Sodium hydrogen carbonate

 

List some of the uses of this chemicals?

Baking

Tooth paste

cleaning

 

2. Add 1 spoonful of Chemical B (Calcium chloride) on the right side of the zip-lock bag.  Do not mix the chemicals.  Describe and record the properties for Chemical B.  

What is it’s formula?

 

Calcium chloride

 

List some of the uses of this chemicals?

In plastics

Treatment in plants

Prevents ice from freezing the road

In caned vegies

2. How is chemical B different from Chemical A? –
3. Look and describe Chemical C (Bromothymol blue).  Record your observations in the space provided below. 

What is it’s formula?

Bromothymol blue (it is stain)

 

List some of the uses of this chemicals?

 

It is testing for photosynthesis and respiration

Measure the presence of carbonic acid in a liquid

 

 

 

Now you are ready for the observations of change. 

1. Mix a small amount, not all of it, Chemical A with Chemical B in the middle zip-lock bag.  Record observations.  
3. No change it was like putting pebbles into sand
10. Add 10 mL of chemical C into a plastic bag.  QUICKLY remove as much air as possible and then seal it up.  In the first 30 seconds, squeeze the bag in various places to mix the chemicals. What do you observe? Take a photograph and if possible video recording.

 

 

It got extremely hot when chemical c was mixed in to both chemical a and B and it tourned into an orangy colour

 

 

1. Detect any temperature changes with your hand.

 

Hot to touch and humid when I took it off

5. After 2 minutes thoroughly record any new observations.
7. No new observations but the pebble-like things dissolved a little bit and shrunk in size
10. In the space below add at least two photographs of your zip-lock bag.

 

 

 

1. When you are finished, wash all the chemicals down the drain and rinse out the plastic bag. Discard the UNSEALED bag in the correct discard.  DO NOT take off your goggles until everyone in the room has completed the lab.

 

1. What evidence of chemical change did you observe in the bag? 
3. The chemicals became hot and bubbly and I was informed that it is corrosive material
9. What physical changes did you see? Answer in complete sentences.  

 

 I observed that the color of the chemicals turned orange and the blue dye was nowhere to be seen. It resembled to scrambled eggs before cooking.