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Feedback Comments on Matter

by Ron Kurtus

A total of 255 comments and questions have been sent in. They are listed according to date.

List of most recent 10 letters




Atom as Solar System Role of moons in theory India
Kinetic Theory of Matter Relationship between Brownian motion and Kinetic theory USA
Dry Ice Difference between vaporization and sublimation Kenya
Atoms Is an atom electrically neutral? Nigeria
Density Finding the density of an object Tanzania
Kinetic Theory of Matter What is a solid, liquid and gas? India
Atom as Solar System Why isn't the solar system a giant atom? USA
Density Factors How physical conditions affect density USA
Evaporation How are water molecules able to escape gravity? USA
Changing States of Matter What if matter did not change its state? Pakistan

Next 10

Role of moons in theory

Topic: Atom as Solar System


September 9, 2019

1 how would the moon plays role in the given theory?
2 what would change in the theory if e considered 9 planets?
Or change to 12 planets?>

majid - India



The Solar System model of an atom looks at electrons moving around the nucleus of the atom. However, in most solar systems, many planets also have one or more moons revolving around the planet. This presents a problem with this model, since electrons are primary particles that cannot be subdivided.

Also, according to Quantum Mechanics, the sub-atomic particles can be viewed as wave-forms.

Thus, this model is simply convenient way of looking at the Solar System.

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Relationship between Brownian motion and Kinetic theory

Topic: Kinetic Theory of Matter


July 9, 2019

What is the relationship between Brownian motion and the Kinetic Theory of Matter?

Your content is rich on the topic.

Emmanuel - USA



The Kinetic Theory of Matter states that matter is composed of a large number of small particles—individual atoms or molecules—that are in constant motion.

On the other hand, Brownian motion is the erratic random movement of microscopic particles in a fluid, as a result of continuous bombardment from molecules of the surrounding medium. Thus Brownian motion concerns the collisions of particles in motion due to the Kinetic Theory of Matter.

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Difference between vaporization and sublimation

Topic: Dry Ice


October 11, 2018

Differentiate between vaporization and sublimation

Kevin - Kenya



Vaporization is the process that occurs when a chemical or element is converted from a liquid or a solid to a gas.

When a liquid is converted to a gas, the process is called evaporation or boiling.

When a solid is converted to a gas, the process is called sublimation. This is what happens with dry ice (frozen carbon monoxide gas).

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Is an atom electrically neutral?

Topic: Atoms


April 26, 2018

An atom is said to be electrically neutral?

melody - Nigeria



It is true that an atom is electrically neutral, because it has the same number of positive (+) and negative (-) particles.

See Structure of the Atom for more information.

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Finding the density of an object

Topic: Density


April 15, 2018

1. An object with the volume of 150 cubic centimetre has a percentage of volume submerged of 60% when immerse into water. What is the density of the object?

can I get books of supplement material which have enough questions on densities, relative densities etc

Denis - Tanzania



If 60% is submerged in the water, that means that the volume of water displaced is 150 * 0.6 = 90 cc. Since the density of water is 1, the mass of 90 cc of water is 90 g.

Thus, the mass of the object is the mass of the displace water 90 g divided by 0.6 equals 150 g.

The density of the object is its mass divided by its volume or 150/90 = 1.67.

That seems to be a round-about way, but I hope it explains the subject.
Also refer to: Density of Matter and Factors Affecting Density of Matter.

Best wishes for success in your studies.

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What is a solid, liquid and gas?

Topic: Kinetic Theory of Matter


November 7, 2017

Q1. What is solid, liquids, gas

MD - India



See States of Matter for an explanation.

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Why isn't the solar system a giant atom?

Topic: Atom as Solar System


October 5, 2017

I had a question about the article you wrote regarding Bohr's Model of an atom. Why do you disagree with the fact that our solar system can't be just one "giant" atom. I was hoping to get in touch with you to discuss this?

Tristan - USA



Although our solar system looks like it could be a giant atom, there are a number of problems in the analogy. One it that electrons in an atom have an electrical charge, while there is nothing similar in the solar system. Also, the nucleus of an atom is made up of protons and neutrons, while the Sun is a mass of hot gases.

On the quantum scale, atomic particles are not tiny spheres but are wave packets.

Still, the similarity between the solar systems and atoms is intriguing.

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How physical conditions affect density

Topic: Density Factors


September 30, 2017

Describe how physical conditions affect density

kiprotich - USA



Density is mass divided by volume. Compressing an object decreases its volume and thus increases its density.

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How are water molecules able to escape gravity?

Topic: Evaporation


September 22, 2017

How are water molecules able to escape gravity? In other words, gravity withholds H2O from leaving the surface of the earth, but that same body of water evaporates and those molecules are unaffected by gravity.

Travis - USA



With water, the velocity of the molecules is not great enough to overcome their molecular attraction, and thus the material is a liquid that is kept toward the surface of the Earth. However, when H20 becomes a gas, the velocities of the molecules is much greater, such that they move about freely.

Most of those molecules velocities that are low enough to be constrained to the Earth's atmosphere. But some of the molecules of the gas or steam become accelerated due to radiation from the Sn, such that they have enough kinetic energy or velocity to escape the Earth's gravity.

Fortunately, the loss of water vapor molecules into space it very small.

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What if matter did not change its state?

Topic: Changing States of Matter


August 25, 2017

Explain that what happened if there would be no change in states of matter?


Aamish - Pakistan



If all matter stayed in its existing state or phase, ice would not melt to become water, and water could not boil into steam. Also, there would be no evaporation of water. Just these factors alone would affect living beings in a short time.

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