A scientific explanation is the scientific way of explaining phenomena we observe by supporting a claim about what we observe with evidence and reasoning. What are phenomena? Phenomena are things, events, or circumstances that can be studied and observed. Octopus mimicry, gravity, and global warming are all examples of phenomena. We can study and observe these things, events, and circumstances using our five senses, and/or with scientific tools and technology.
On the other hand, ghosts, UFOs, and Big Foot are not considered phenomena. Only a select few people claim to have observed these things, but even the fanciest technology and equipment have yet to be able to study, much less detect, these things.
Scientists do not develop scientific explanations of things that are not considered to be phenomena. This is simply because we cannot gather evidence, which is a critical part of a scientific explanation.
However, there are plenty of phenomena that we cannot see, but that we can still detect and study. Black holes are an example of such phenomena. A black hole is a place in space where gravity is so strong that even light cannot escape. Because no light can get out, people cannot see black holes. They are invisible to the human eye.

Claim:
Sometimes scientists make a claim (answer to the question) about phenomena before collecting evidence through an experiment via observations and background research. Other times, scientists collect as much evidence as possible first in order to make a valid claim. In this case, we collected the evidence first.
Evidence:
In order to answer this question (make a claim), we first had to collect evidence. Below are the procedure we used to gather evidence.
1. Copy the table in your science notebook (below).
2. Measure the mass of the balloon (with no air) on the triple beam balance. Record the unit.
3. Blow up the balloon until the circumference is 30-40 cm. Tie a knot. Measure and record the mass of the balloon in the table below. Record the unit.
4. Blow up another balloon until the circumference is 50-60 cm. Tie a knot. Measure and record the mass of the balloon in the table below. Record the unit.
In order to make sense of our evidence to answer the question, "Is air matter?", we had to do background research to understand what defines matter. According to Glencoe NY Science Grade 7, "Matter is anything that takes up space and has mass".
Therefore, since the amount of space the balloon took up (volume) and mass increased as we blew more air into the balloon, we can make the claim that "air is matter".
Air is matter (claim). We found that the mass of the balloon increases each time we blew more air into it. When the balloon had no air, it had a mass of 1.9 g. When we blew the balloon to 35 cm, the mass went up to 2.1 g. Finally, when we blew the balloon to 55 cm, the mass increased even more to 2.4 g (evidence). According to Glencoe New York Science Grade 7 (pg.243), “Matter is anything that takes up space and has mass”. Therefore, the increasing size of the balloon and mass show that air takes up space and has mass, which are the defining characteristics of matter (reasoning).

Claim:
Sometimes scientists make a claim (answer to the question at hand) about phenomena before collecting evidence through an experiment via observations and background research. Other times, scientists collect as much evidence as possible first in order to make a valid claim. In this case, we collected the evidence first.
Evidence:
In order to answer this question (make a claim), we first had to collect evidence. Below are the procedure we used to gather evidence.
1. Record as many qualitative observations of each liquid as you can.
2. Measure and record the mass (with the unit) of liquid A and B.
3. Measure and record the volume (with the unit) of liquid A and B.
4. Calculate the density of liquid A and B by dividing the mass of each liquid by the volume of each liquid. The unit is g/mL.
In order to make sense of our evidence to answer the question, "Are the two liquids the same?", we had to do background research to understand the unique properties of liquids. According to Wikipedia.org, "different materials usually have different densities". Furthermore, according to middleschoolchemistry.com, "“…each substance has its own density because of the atoms and molecules it is made from.”
Therefore, since the density of the two liquids were different, we can make the claim that the two liquids are different.
The two liquids are not the same (claim). Although both liquids were clear, we found that the two liquids had different odors. Liquid A had a harsh, burning odor, while liquid B had a more sour odor. Furthermore, when we calculated the density of each liquid, we found that liquid A had a density of 0.8 g/mL, while liquid B had a density of 1.05 g/mL (evidence). According to Wikipedia.org, "different materials usually have different densities". Furthermore, according to middleschoolchemistry.com, "“…each substance has its own density because of the atoms and molecules it is made from.” Therefore, since odor and density are properties unique to different materials, we know that the two liquids are different.
Scientists develop scientific explanations of phenomena. This is because phenomena are things we can observe, study, and things of which we can collect evidence. This coming school year, you will hear the word "phenomena" regularly. When you hear about stories of ghosts and UFOs this coming Halloween, be a scientist and ask the story teller... What is your evidence? What is your reasoning?!
Answer the questions below in complete sentences.
1. What are phenomena?
2. What are two examples of things that are considered phenomena? Why are they considered to be phenomena?
3. What are two examples of things that are not considered to be phenomena? Why are they NOT considered to be phenomena?
4. Why don't scientists study things that are not phenomena?
5. Are black holes considered to be phenomena? Why or why not?
6. Do scientists always make a claim (hypothesis) before collecting evidence? Explain.
7. How do we know air is matter?
8. How do we know the two liquids are NOT the same?
9. Explain how background research helped us to develop our scientific explanations to the questions, "Is air matter?", and "Are the two liquids the same?".
Extension Question
10. Write 3 facts about black holes after watching the following video: http://www.space.com/15421-black-holes-facts-formation-discovery-sdcmp.html