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Colours and acidity

Rationale and Core Concepts

Colour Acid/Base Colour mixing (misconceptions) Transportation of water in a plant

We chose this activity because it is impressive and interesting for children.

Materials are easily available at home

It can be adapted to various age groups

Active learning

Expected Outcomes

That the children will be able to understand how acids and bases react with a variety of substances

That the children will understand that there are exceptions to the rules of colour mixing

That the children will understand how water travels in a plant and how it takes minerals and nutrients from the ground.

Target Group, Setting, Space and Time

10-12 year olds

Laboratory/ Home

2 lessons

Activity 1 – Acidity and Baseness (Home)

The children and parents/guardians will boil a small amount of red cabbage.

They will drain the water into five separate transparent cups

They will add vinegar to one of the cups and note the change of colour.

They will add baking soda to 3 of the other cups in varying amounts (given by the teacher) creating the colours blue, yellow and green.

They will then mix the red solution with the yellow solution and note the colour change

Activities (1)

Activities (2) Activity 2- Water Transport in a Plant (Classroom)

The children will place water in the cups

The children will place some different food colourings in the cups

They will then place white flowers in the cups and wait about two hours

The children will observe the change ( the flowers absorb the water as always, but as it was colourful the flower will show this colour change)

Activities (3) Activity 3- Discussion (Classroom)

Vinegar/soda and acid/base

Conceptions of colour change were questioned?

Poppy vs. Corn flower

Water transport

Materials Activity 1

Red cabbage

Five transparant cups Vinegar Baking soda

Activity 2 White flowers Cups Water Food colouring

References Activity 1. Red Cabbage Indicator

chemistry.about.com/od/acidsbase1/a/red-cabbage-ph-indicator.html

Activity 2. Flower Colouring

O Lugar dos Amiguinhos

encontrodeamiguinhos.blogspot.gr

Famous Italian director