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Feedback Comments on Matter

by Ron Kurtus

A total of 244 comments and questions have been sent in. They are listed according to date.

List of most recent 10 letters




Dry Ice Using CO2 for supercritical extraction USA
Dry Ice Info on dry ice USA
Density What is the calculation of density? South Africa
Pressure and States of Matter Explain pressure in gases and liquids Nigeria
Kinetic Theory of Matter Melting and boiling points of materials USA
Atom as Solar System Thinking of Big Bang Theory Australia
Density Factors Wants to rmaintain the strength of a iron pipe India
Floating Density of object is equal to liquid USA
Changing States of Matter Converting matter Tanzania
Changing States of Matter Why does temperature remain constant? USA

Next 10

Using CO2 for supercritical extraction

Topic: Dry Ice


January 29, 2017

I would like to discuss some commercial uses for Dry Ice and it's conversion to Co2 for supercritical extraction.
Please let me know if you are available to discuss.

Thank you in advance,

Gary - USA



Dry ice is a convenient source of CO2. Allowing the gas from the dry ice to heat to about 31 degree C should help in the supercritical extraction process.

I hope that helps. Unfortunately, I am not an expert in this field.

Best wishes for success in your work.

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Info on dry ice

Topic: Dry Ice


March 11, 2016

To whom this may concern,

I am a sixth grader at Kennedy Middle School. Our school is participating in something called Genius Hour which allows us to research a topic that interests us. We are required to interview a professional who is knowledgeable about our topic. My topic is dry ice.
If you could please answer the questions below as soon as you get the chance, it would be greatly appreciated. Thank you for taking time out of your day to respond to this email.

Thank you for your time,

Gianna G.

My questions are:

Where was dry ice first found?

How long does dry ice last in water?

What gas is given off of dry ice?

How is dry ice created?

What is inside dry ice?

How long can you touch dry ice with bare hands?

Can you make dry ice?

Gianna - USA



Dry ice was first observed in 1835 in France. It is frozen carbon dioxide (CO2). When it melts, it turns to CO2 gas. You should only hold dry ice a fraction of a second. Special equipment is used to make dry ice.

See our lesson on Dry Ice is the Solid State of Carbon Dioxide for more information. Also see Dry Ice Wiki for detailed info.

Best wishes for success in your report.

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What is the calculation of density?

Topic: Density


February 23, 2016

calculation of density

sello - South Africa



The density of an object is its mass divided by its volume.

Since the density of water is 1.0, you can find an object's density relative to water by comparing its weight to the weight of an equal volume of water.

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Explain pressure in gases and liquids

Topic: Pressure and States of Matter


February 16, 2016

explain vapour
pressure and explain the principles of pressure
measurement in liquid and in gases

okpu - Nigeria



Vapour is the gaseous state of matter. It is like steam.

Meters can compare water or air pressure with some standard. A barometer is an example of a meter that measures air pressure.

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Melting and boiling points of materials

Topic: Kinetic Theory of Matter


January 30, 2016

Hello! My name is Connor Feckett. I am a student at the School of Applied Research in Land O Lakes. I am currently working on a project about the changes in matter and using the scientific method. This project will include researching the different states of matter, kinetic theory of matter, melting and boiling points, as well as using the scientific method to predict if adding things to water may change its melting or boiling points. I am wondering if you could help direct me where to find the melting and boiling points of at least 5 different things. I appreciate your time. Thank you.




See Melting and Boiling Points of Common Materials for a comprehensive list.

Best wishes for success in your project.

PS: I'm originally from Wisconsin.

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Thinking of Big Bang Theory

Topic: Atom as Solar System


January 24, 2016

Finally.... I came up with this "theory" on my own several years ago but being that I'm no scientist or physicist or whatever, it was kind of silly of me to believe I was the only one. I could never find anything anywhere on the net though (I guess I was googling the wrong questions) but to add fuel to the fire, what about the Big Bang??? When we conceive, first there is nothing, sperm and egg come together then a mini explosion and BAM, cells appear out of nothing and start to multiply. Wasn't the Big Bang kind of the same, first there was nothing, then a mini explosion (not so mini to us) and BAM, galaxies appeared out of nothing and started to multiply. I know this is all impossible to prove but when you really stop and think about it, it makes a hell of a lot more sense than the magical invisible man in the sky who will punish us for all eternity if we do something wrong, but he loves us.... Doesn't it?

Are there any sites or groups or something on this subject apart from this page that you know of? Is there a specific name for this "theory" (if that's what it is)

Thank you so much for being here, it's a relief to know I'm not the only one who thinks this way.

Paul - Australia



The Big Bang Theory supposes that all the matter in the Universe was compressed into a compact ball when something triggered it to explode and spread out the matter, which then collected together as stars, galaxies, and other objects.

The Multiverse Theory states that there were many such explosions and many other universes besides our own.

With conception, the sperm and egg are really highly complex living cells that combine and start to grow into a human. However, it might be possible that two different compact balls of mass met and then exploded into our Universe. That might be a good explanation of why the Big Bang occurred.

I'm sure there are groups interested in the Big Bang Theory in Facebook or through MeetUp.

Best wishes in your studying these things, and keep up your curiosity.

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Wants to rmaintain the strength of a iron pipe

Topic: Density Factors


December 15, 2015

sir we have steel tubing pipe having dia of1" and thickness 3mm and density of 7850. so can we reduce its density. or is there any way to reduce the weight of tube without changing strength....

sachin - India



The density of the pipe is set by its weight and volume. You might be able to reduce the weight of the pipe and adding a matrix around it to maintain its strength. However, it might be easier and less expensive to consider a different type of tubing. Best wishes in solving your problem.

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Density of object is equal to liquid

Topic: Floating


December 14, 2015

If the density of a body is equal to the given liquid then what will happen .? And how.?




Density is the mass divided by the volume. See Density of Matter.

If the density of an object is greater than that of the liquid, it will sink. If its density is less, it will float to the top. If the density of the object is the same as the liquid, it will stay somewhere within the liquid.

See How Objects Float in Fluids for more information.

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Converting matter

Topic: Changing States of Matter


December 8, 2015

Explain how can matter be converted into another matter specify the process involved




You can change the state or phase of a material from solid to liquid to gas and back by applying heat or cold.

However, one material cannot be changed to another material. Iron cannot be changed to copper.

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Why does temperature remain constant?

Topic: Changing States of Matter


December 2, 2015

I am teacher of 6th graders learning about phase of matter change. I am having trouble explaining why the temperature remains the same while freezing is happening. Any help would be appreciated. Thank you

mary - USA



I just added an explanation at Temperature Constant During Phase Change. I hope that helps. Let me know if it clarifies things for your students.

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