DIY pH Indicators: Turn Your Kitchen Into a Chemistry Lab!

Turn your kitchen into a chemistry lab by making your own DIY pH Indicators!

pH is a measurement of how acidic or basic something is on a scale of 0-14. 

 

Testing how acidic or basic something is with a color-changing indicator is a staple of many chemistry experiments. Now you can try it too! Turn your kitchen into a chemistry lab with DIY pH indicators!

 

A substance with a pH of 7 (like distilled water) is neutral. A substance with a pH of less than 7 is an acid. The closer the number gets to zero, the stronger the acid is. A substance with a pH of more than 7 is a base. The closer the number is to 14, the stronger the base is.

 

Try making one of these two natural DIY pH indicators and use it to test the pH of things you find around your home!

 

Recommend Age: 8+ with adult help for chopping and boiling.

Materials you will need for a red cabbage pH indicator:

  • Red cabbage
  • Knife and cutting board
  • Warm water
  • Blender
  • Strainer or funnel with coffee filter
  • Container to collect indicator


WARNING: Cabbage and blueberry juices can stain clothes! Mess-friendly play clothes or coverings such as aprons are recommended for this activity.

You can can make a variety ph indicators with Orlando Science Center

Directions for making red cabbage pH indicator:

STEP 1
  • Peel 3 or 4 big leaves off a head of red cabbage and chop the leaves into small pieces.
  • Fill a blender halfway with hot water.
  • Add the chopped cabbage leaves to the blender.
  • Blend the leaves and water on high until the liquid turns purple and all the leaves are blended.

    *Alternatively, you can boil the chopped leaves in just enough water to cover them for a few minutes, then let steep for 30-60 minutes.

Red cabbage for DIY pH indicators
STEP 2 
  • Place a strainer or funnel lined with a coffee filter over a container to collect the indictor, such as bowl, pot, or bottle.
  • Pour the mixture through the strainer to remove the cabbage pulp.
  • Push down on the pulp in the strainer with a spoon or spatula to squeeze out more liquid.
strain blended cabbage for purple diy ph indicator
STEP 3
  • The purple liquid in your container is your indicator solution. The exact color will vary depending on the pH of the water you used.
  • Experiment with the indicator using the ideas below!
  • Red cabbage indicator can be saved in a sealed container in the refrigerator for up to 1 week.
Result of blending red cabbage to create diy ph indicator

Materials you will need for a blueberry pH indicator:

  • 200g blueberries
  • Masher, spoon, or spatula to mash blueberries
  • Water
  • Pot
  • Strainer or funnel with coffee filter
  • Container to collect indicator

Directions for making blueberry pH indicator:

STEP 1
  • Mash the blueberries in a bowl or pot to release the blueberry juice.
  • Add mashed blueberries, juice, and a half cup of water to a pot.
  • Boil the blueberries for 5-10 minutes. The blueberry juice will turn red-purple.
Mash and boil blueberries to make a blue DIY ph indicator
STEP 2
  • Place a strainer or funnel lined with a coffee filter over a container to collect the indictor.
  • Pour the mixture through the strainer to remove the blueberry skins.
  • Push down on the skins in the strainer with a spoon or spatula to squeeze out more liquid.
  • The purple liquid in your container is your indicator solution. The exact color will vary depending on the pH of the water you used.
result of using blueberries to make another diy ph indicator

What to do with your DIY pH indicators 

Now that you have your pH indicators, it's time to get to testing! Use household liquids such as salt or distilled water, different fruit juices, milk, liquid detergent or soap, and more!

  • Add each of the substances you would like to test to the cups. (Only add one substance to each cup.) 
  • Add a spoonful of indicator to the first cup, and stir the indicator into the substance.
  • Observe the color changes. What do you see? Encourage your scientist to write down what color each substance turns. You can use crayons or markers to help keep track of color changes.
You can use different household liquids to test you DIY indicators

Expand on the Activity:

  • What color changes did you see? Did you notice any patterns?
  • If you use vinegar or lemon juice, what do you think will happen to the color of the DIY pH indicator if you add baking soda or an antacid tablet

  • For another hands-on chemistry experiment, try making your own STEM slime activity

The Science: pH and pH indicators

  • pH is a measurement of how acidic or basic something is. It is measured on a scale of 0-14.
  • A substance with a pH of 7 (like distilled water) is neutral. A substance with a pH of less than 7 is an acid. The closer the number gets to zero, the stronger the acid is. A substance with a pH of more than 7 is a base. The closer the number is to 14, the stronger the base is.
  • Strong acids and bases can be very dangerous, while weaker acids and bases (those with a pH close to 7) are safer to use.
  • We find acids in many of the foods we eat, as well as in our stomachs. Acids found in foods give them a sour taste.
  • Bases are commonly found in cleaning products and antacid medications. Bases feel slippery and are rare in food because they taste bitter. For reference, think about the taste of soap!
  • pH indicators are compounds that change color in the presence of an acid or a base.
  • Different pH indicators have different ranges. Some may only be able to show whether something is acidic or basic, while others may have a wide range of colors that can show different strengths of acids and bases. Some may be better for showing the pH of acids, while others may be better at showing the pH of bases. In a lab, the best indicator to use depends on the pH range you want to see.

Learn More: Chemistry

  • There are several different definitions of acids and bases in chemistry.
  • A simple chemical definition of an acid is a substance that releases hydrogen ions (H+) when dissolved in water. A simple chemical definition of a base is a substance that makes hydroxide ions (OH-) when dissolved in water or a substance that takes hydrogen ions from an acid.
  • Ions are positively (+) or negatively (-) charged particles of an element.
  • Many red, purple, and blue plants contain chemicals called anthocyanins, which are weak acids that dissolve in water and change color in response to changes in pH. Because of this, plants with anthocyanins like red cabbage and blueberries can easily be made into pH indicators.

Did you make and test your own indicator? We’d love to see how it turned out! Snap a photo of you making or experimenting with your indicator and submit it to our Science Showcase here or use #OSCatHome on social media!

OSC At Home Emails

Get a round up of our latest activities and ideas delivered straight to your inbox so you don't miss a thing!

Find out when we release new resources by following us on social media!

 

Follow us on social media for even more science fun including fun facts, games, behind-the-scenes photos, and more!

 

Facebook Logo Instagram Logo YouTube Logo Twitter Logo

Support OSC At Home

In these ever-changing times, it is our pleasure to adapt quality Orlando Science Center experiences to engage with everyone while they are safe at home. Please consider supporting our operating fund to ensure we can continue developing resources today and well into the future. Thank you for your generosity and support!

How to Make Marbleized Paper to Create Custom Cards and Artwork

Create a stunning masterpiece when you follow these step-by-step instruction for how to make marbleized paper – a sensory STEAM project for kids and adults alike!


It’s always fun to use materials in new ways, and this is likely one way you’ve never used shaving cream before! Use our directions for how make marbleized paper and follow along with the questions included to help you make observations as you create! Not only will you have a wall-worthy finished project, you'll also learn some neat STEM skills along the way. 

Materials:

  • Shaving cream 
  • Paper (start with a heavier weight paper, like cardstock or construction paper) 
  • Food coloring* or washable paint such as liquid watercolor or tempera paint
  • Popsicle sticks 
    (If you don’t have popsicle sticks, read the directions
    carefulland substitute in a different tool. Tooth picks are great for creating the marble effect and a ruler or spatula work well to remove the shaving cream from your paper at the end!)

 

*Warning: Food coloring can stain! If you're worried about mess, substitute washable paint. Either way, mess-friendly play clothes are recommended for this activity!

Material for how to make marbleized paper

Directions:

STEP 1
  • Spray some shaving cream onto protected work surface.
STEP 2 
  • Spread the shaving cream out so it’s about ½ an inch thick.  

    How does the shaving cream feel? Is it a liquid or a solid? Do your best to describe it. 
Spread shaving cream onto protected work surface
STEP 3
  • Add a few drops of food coloring on top of the shaving cream. Make sure you leave some space between each drop. 

    What do you observe as you drip the food coloring onto the shaving cream? Does it mix in? Does it sit on top? Sink to the bottom? Spread out flat? What do you see happening? 
Add dye to shaving cream make marbleized paper
STEP 4
  • Use a popsicle stick to drag the food coloring around on the top of the shaving cream, creating a marbled effect. 

    Do the colors mix with the shaving cream? Do they stay separate? Do they mix with each other? 
Swirl shaving cream colors together to make marbleized effect
STEP 5
  • When you’re happy with the marble you’ve created, place your paper on top of the shaving cream and food coloring and gently press down. Depending on how thick your paper is, you may see the marble start to show through the other side. Let it sit for about 5-10 seconds.  
STEP 6
  • Carefully remove your paper and place it shaving cream side up on a protected work surface. 
Place paper on shaving cream to create marbleized paper effect
STEP 7
  • Use a popsicle stick to very gently scrape the shaving cream off your paper. This will likely take a few passes and it may help to remove the shaving cream from your popsicle stick between each pass.

    The food coloring has soaked into your paper, leaving behind a marbled pattern! How is the design on your paper similar to the design you saw on your shaving cream? How is it different? 

STEP 8
  • Let your paper dry for a few minutes. Once dry, use a tissue or paper towel to brush off any leftover little bits of shaving cream.
Swirl shaving cream colors together to create marbleization

Display your marbleized paper with pride, or add it to a larger project! Be sure to share your mess-terpieces with us by submitting them to our Science Showcase here or tag Orlando Science Center and use #OSCatHome on social media! You might be featured on our channels. 

 

NOTE: It’s best to let the paper dry completely before cutting it or writing on it.

Expand on the Activity!

  • Try this again and try using more or less food coloring. How do your results change? 
  • Test out different kinds of paper. What happens when you try this with printer paper, newspaper, tissue paper, cardboard, or colored construction paper? What kind of paper works best? 
  • Experiment with making different shapes and patterns with the food coloring in the foam. How many different patterns can you make? 

OSC At Home Emails

Get a round up of our latest activities and ideas delivered straight to your inbox so you don't miss a thing!

Find out when we release new resources by following us on social media!

 

Follow us on social media for even more science fun including fun facts, games, behind-the-scenes photos, and more!

 

Facebook Logo Instagram Logo YouTube Logo Twitter Logo

Support OSC At Home

In these ever-changing times, it is our pleasure to adapt quality Orlando Science Center experiences to engage with everyone while they are safe at home. Please consider supporting our operating fund to ensure we can continue developing resources today and well into the future. Thank you for your generosity and support!