These are three questions each with its complete answer.
Question 1. Something must have mass in order to create change.
A. True
B. False
Answer:
- <u><em>False</em></u>
Explanation:
Two counter examples will prove that the statement is false.
- light and fire
Neither light nor fire have mass, so they are not considered matter, but yet both can create changes.
Light is an electromagnetic wave, so it is energy, and as such it, of course, can cause some changes. One example are the chemical reactions, like photosynthesis, which require light to happen.
Ligth may also be described either as quanta named photons. Although photons behave like particles they do not have mass.
So, that example contradicts the statement that something must have mass in order to create change.
Fire also contradicts the statement. Fire is a manifestation of energy, it does not have mass, and sure you know how fire create changes in living and no living things.
Question 2. Powdered medicine fills a pill capsule. Which of the following is the best description of the state of the powder?
A. It is a solid because all powders are solid.
B. It is a gas because it takes up the entire volume of the pill capsule.
C. It is a liquid because it does not hold a definite shape.
Answer: the best description is the choice A:
- A. It is a solid because all powders are solid.
Explanation:
Indeed, although sometimes the powder may be very fine (dust), yet it is not liquid or gas. Powders are always solid.
There are four main states of matter: solid, liquid, gas, and plasma.
Liquids are able to take the form of the container but do not occupy the entire container. Gases do occupy the entire container.
When powder is very fine it could resemble some properties of liquid, but the structure of powders is not crystaline, this is it is not an ordered arrangement. The structure of powders is an ordered arrangement, so powders are solids and not liquids.
It is easy to discard that a powdered medicine could be a gas, because it definetly do not occupy the entire volume of the pill capsule.
Question 3. Find an example of something that you do NOT know the state of. Describe it, and tell me your best guess of what state it is. Explain your guess.
Answer:
Two examples come to my mind:
- A paste like Nutella or toothpaste
- Wax of a candle
Explanation:
I will use the example of Nutella to complete the answer.
Nutella is not a gas because when you open the jar it will not escape and fill the room around it.
When you put Nutella in a plate it will not flow over the whole plate, is it a solid ? But yet you can spread it easyly over a cookie. Is it a liquid?
So, Nutella behaves like a solid until you apply some force over it and then it seems a liquid.
I would guess that pastes are solids because they should have an inner structure that keep the particles together.
If you do some research you will find that pastes are neither liquid nor solids, they are named gels. And gels may be seen as a dispersion of molecules of a liquid within a solid, i.e. in liquid particles dispersed in the solid medium
This sure meets the requirements of this question.
