Posts Tagged ‘science’

#12 Testing Charles’s Gas Law

Monday, October 20th, 2014

charles's-gas-lawThis post contains affiliate links. I was compensated for my work in writing this post.

My kids tested Charles’s Gas Law with a fun experiment involving a glass soda bottle and a balloon. We are using Christian Kids Explore Chemistry by Bright Ideas Press. This is one of the experiments in the book.

What is Charles’s Gas Law?

I suppose we should define Charles’s Gas Law before we conduct our experiment. Charles’s Gas Law: If the temperature of a gas is increased, the volume of the gas will increase.

Knowing this law will help you predict what will happen when you place a glass bottle in the refrigerator, then set it in a bowl of boiling water with a balloon over it. The gas inside the bottle went from cold to hot, which means the air inside the bottle is expanding. This is the reason the balloon immediately stands up, because the expanding air needs to go somewhere.

balloon-experiment

Then you place the bottle into ice water, and see the balloon deflate again. You might need to place it in the refrigerator to see the full effect of the deflated balloon.

Steps for Charles’s Gas Law Experiment

  1. Place a glass bottle into the refrigerator for at least one hour so the air inside it is nice and cold.
  2. Place some hot (not boiling–it melted our first balloon!) water in a bowl, and place ice water in another bowl.
  3. Grab the bottle out of the refrigerator and put the balloon on the top of it.
  4. Place the bottle into the hot water and watch the balloon stick up suddenly.
  5. Now place it into the ice water. Wait for a while, and notice there is less air pressure in the balloon.
  6. Place the bottle back into the fridge, and an hour later, voila! A limp balloon will cause your kids to squeal and point. Indeed, Charles’s Gas Law is correct!

Video of the Experiment

Take a look at the experiment:

The bottle is too small to actually inflate the balloon for real, but I’ve done a similar experiment, throwing dry ice into the bottle and placing a balloon over the top. The air expands way more explosively, and the balloon actually inflates!

*Always make sure to wear gloves when touching dry ice.*

#11 Measuring the Volume of a Solid

Monday, October 13th, 2014

meauring-the-volume-of-a-solid

This post contains affiliate links. I was compensated for my work in writing this post.

What happens when you have weird-shaped objects, and you want to know their volume? Find out a clever way to do just that! We will be measuring the volume of a solid in our experiment today. My younger two children are using Christian Kids Explore Chemistry by Bright Ideas Press, and this is one of the fun experiments in the book.

Grab three interesting-shaped rocks from your backyard, and label them A, B, and C with a permanent marker. Grab a glass measuring cup and pour 300 ml of water into it. Now you will want to place one rock into the water. Measure how much the water went up. How high is the water now? Write it down. Then subtract the number from the original number (300 ml). You will find out the volume of the rock! Whatever amount of water the rock displaced is the amount of space it filled up, or its volume.

Remove Rock A from the water and measure Rock B in the same way. Was the rock smaller, larger, or the same volume? What about Rock C? Our third rock had the largest volume of the three rocks.

Measuring the Volume of a Solid Experiment

Now you can see how we performed this fun experiment:

Make sure to write down each of your measurements on the chart provided in the book. It helps if you clip the page to a clip board so that you can write your measurements as you are doing the experiment. If you want, you can doodle all over the rest of your page, as if you were a mad scientist!

rock-experiment

#10 Dissolving Calcium with Acid

Monday, October 6th, 2014

dissolving-calcium-with-acidThis post contains affiliate links. I was compensated for my work in writing this post.

Today we will be doing an experiment where we are dissolving calcium with acid. We are using Christian Kids Explore Chemistry by Bright Ideas Press to study elementary-level chemistry. This is one of the fun hands-on activities in the book.

You will need a raw egg, vinegar, and a mason jar. Place the raw egg into the mason jar. Now pour vinegar over the egg until it is completely covered. You might want to put a little extra vinegar over it because the vinegar will evaporate somewhat. Now leave the jar alone for 24 hours.

egg-experimentsIf you look at the egg as it sits in the water, you will notice small bubbles surrounding the egg. This is the acid from the vinegar eating away at the calcium carbonate that makes up the shell of the egg.

egg-experiments-2

After 24 hours, grab the egg gently in your hand. How does it feel? My daughter says it felt soft and squishy. The shell had been eaten away completely by the acid in the vinegar!

You will want to watch the video to see whether the egg in this condition will bounce or splat!

#9 Acids and Bases

Monday, September 29th, 2014

acids-and-bases

This post contains affiliate links. I was compensated for my work in writing this post.

Today we are talking about acids and bases, and we will be doing an experiment to show what happens when you combine an acid and a base. We are using Christian Kids Explore Chemistry by Bright Ideas Press to study elementary-level chemistry this year with my younger two kids.

First we went through the house opening cupboards, trying to find acids and bases. The book gives some examples of chemical names for acids and bases, and you can see if you can find those chemicals by looking at the list of ingredients for household cleaning products and food.

Here are some of the items we came up with:

Acids

  • Vitamin C–ascorbic acid
  • Tomato Sauce–citric acid
  • Face Cleaning Product–salicylic acid
  • Bubble Bath–citric acid
  • Soft drinks–phosphoric acid

Bases

  • Ammonia–ammonium hydroxide
  • Oven Cleaner–sodium hydroxide
  • Baking Soda–sodium bicarbonate

Acids and Bases Experiment

Now we are going to conduct a simple experiment that shows what will happen when you combine an acid and a base:

If you want to see this fun explosion in blue and red, check out these posts:

 

acid-base-reaction

Don’t combine just any acid with any base, or you could create toxic fumes that could kill you.

So what is the difference between an acid and a base? Acids are chemical compounds that donate or give away a proton (hydrogen ion) during a chemical reaction. Bases receive a proton (hydrogen ion) during a chemical reaction. So when you see this reaction with the vinegar and baking soda fizzing, the acid (the vinegar) is giving away a proton, and the base (the baking soda) is receiving the proton. Isn’t that cool?