Show:
REVERSIBLE AND IRREVERSIBLE CHANGES
CHEMICAL REACTIONS
ACIDS AND BASES
WATER
100

Dissolving sugar in water is a(n) ___________________ change

reversible

100

You mix two things together and it fizzes and bubbles. Has a chemical reaction happened? How can you tell? 

Yes. It formed a gas.

100

If something has a pH of 2, it is a(n)  _____________. 

acid

100
Describe surface tension in water 

On the surface of the water, the water particles are stuck together, making the top of the water strong. 

200

Baking cookies is an example of a(n) __________________ change

irreversible

200

How can you test if something is carbon dioxide or if it's just air. 

Lighting a stick and seeing if it will stay lit when exposed to it. 

200

If something has a pH of 10 it is a(n) _____________. 

Base

200
What do you need to do to float a penny? 
lay it totally flat to not break the surface tension
300

Melting a popsicle is an example of a(n) _______________ change. 

reversible

300

What are two signs that let us know that fire is a chemical reaction. 

  • Change in temperature

  • Change in odour

  • Change in colour

  • Produces a gas

  • Produces light

300

When pouring cabbage juice into an acid, what colour will it turn? 

Red

300

How can water striders walk on water?

They use the surface tension.


400

Define what a reversible change is and give an example.

A change that can be undone
Ex: melting, freezing, evaporation, condensation, dissolving, blowing up a balloon, molding clay.....

400

What is the difference between a physical and chemical change? 

A physical change is only changing how something looks

A chemical change is changing the chemical make up of something, and making something new that wasn't there before. 

400

When pouring cabbage juice into a base, what colour will it turn? 

Blue/Green

400

Describe cohesion

Water molecules are attracted to each other and stick together. 

500

Define what an irreversible change is and give an example

A change that can NOT be undone

ex: baking, cooking, burning, breaking, elephant toothpaste.......

500

What are the six ways to know that a chemical reaction has happened? 

Formation of solid

Formation of gas

Produces light

Change in temperature

Change in colour

Change in odour (smell)

500

If you pour cabbage juice into a liquid and it stays purple, the liquid is _____________. 

neutral
500

Put the following in order from most cohesion to least cohesion 

oil, rubbing alcohol, water

water, oil, rubbing alcohol