logo
episode-header-image
Aug 2022
28m 3s

What is white?

Bbc World Service
About this episode

Have you ever wondered why waterfalls appear white when still water is transparent? Why clouds, or snow, appear white when they too are essentially just water molecules in different states? What makes something white, opaque or transparent? These are the questions CrowdScience listener Gerardo has been pondering ever since taking in the beauty of fallen water on a hiking trail in his home of Cantabria, Northern Spain. Presenter Marnie Chesterton, sets off on a quest to find out the answers to all of those questions and more. What even is white? Is it a colour, the absence of colour or all the colours of the rainbow combined? Is black really the opposite of white? And what colours do we mix to make white or black paint?

Image: White paint in pots and a paintbrush. Credit: Getty Images

Up next
Oct 9
Are we really in charge?
Have you ever found yourself doing something – perhaps getting a glass of water, eating a snack, or even sitting on the toilet – without remembering making the decision to do it? CrowdScience listener Mohammed certainly has. It’s left him wondering: does he really have free will, ... Show More
26m 28s
Oct 2
How are shells made?
Where do shells come from? CrowdScience listener Tamsyn got in touch, a little embarrassed, confessing that she had managed to reach her twenties without realising that shells are made by living creatures. Suddenly, her curiosity ran wild and she asked CrowdScience to investigate ... Show More
26m 28s
Sep 25
Do plants know we're here?
CrowdScience listener Gurmeet in India wants to know if plants can sense that we're around. She started wondering about this at a wellness centre where she was encouraged to hug a tree. She enjoyed the experience, but what about the tree? Did it enjoy being touched? And is there ... Show More
26m 28s
Recommended Episodes
Jun 2022
What are clouds? And why do they look white?
tail spinning
29m 44s
Jul 2023
The science of snow
<p>Are all snowflakes really unique? What makes some snow better for skiing? And what's the difference between snow and hail? Join Alison Ballance and Katy Gosset as they hit the slopes of Mt Ruapehu and discover a science wonderland of snow.</p><p>You&#x27;ve probably heard the ... Show More
30m 23s
Feb 2022
How does bleach remove color?
<p><strong>#031 Rebroadcast</strong></p> <p>How does bleach bleach stuff? Oh and also, what even is color? This week Melissa and Jam investigate these questions. What's the molecular makeup of color and then how does bleach alter that? How does bleach have enough power to ruin th ... Show More
34m 22s
Jun 2022
The colour conundrum
The world is full of colour! But, listener Maya Crocombe wonders ‘how do we see colour and why are some people colour blind?’Dr Rutherford and professor Fry set out to understand how special light-sensitive cells in our eyes start the process of colour perception, why people some ... Show More
27m 48s
Jan 2022
The weirdness of water, Part 2 of 2
“I don’t really understand why water has so many properties on different scales ranging from very large and cosmic to very small quantum and quarky - Could you help by zooming in and out on water to explain what is known about it? Asks Neil Morton in Stirling.“Why does boiling wa ... Show More
27m 23s
Apr 2024
How pure is the water from your tap?
A recent study on how to get rid of microplastics in water sparked presenter Marnie Chesterton’s curiosity. When she turns on the tap in her kitchen each day, what comes out is drinkable, clean water. But where did it come from, and what’s in it? Dr Stewart Husband from Sheffield ... Show More
28m 12s
May 2018
What Is Red Snow?
Snow usually appears white, but it can come in a few other colors -- and in the case of red snow, that vibrant color may be a warning from Mother Nature. Learn why in this episode of BrainStuff. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudi ... Show More
6m 7s
Oct 2021
The Weirdness of Water, Part 2
“I don’t really understand why water has so many properties on different scales ranging from very large and cosmic to very small quantum and quarky - Could you help by zooming in and out on water to explain what is known about it? "Asks Neil Morton in Stirling. “Why does boiling ... Show More
40m 20s