Scientific Knowledge
Which statement best explains why scientific knowledge improves over time?
A. Scientific data can be interpreted differently based on personal beliefs.
B. Scientific ideas change as new information is collected and interpreted.
C. Scientific theories are considered laws once they are proven by many scientists.
D. Scientific experiments can be repeated under different conditions with the same results
B. Scientific ideas change as new information is collected and interpreted.
What is the main difference between theories and laws?
Theories explain why something happens [with repeatedly confirmed observations], and laws describe what happens.
If a sample of aluminum were reduced to the smallest possible particle of pure aluminum, which statement would most accurately describe the result?
A. The sample would be reduced to atoms of aluminum.
B. The sample would be reduced to molecules of aluminum.
C. The sample would be reduced to protons and neutrons of aluminum.
D. The sample would be reduced to electrons and protons of aluminum.
A. The sample would be reduced to ATOMS of aluminum.
The human body contains a large variety of molecules. However, the human body is made mostly of three elements: carbon, hydrogen, and oxygen. Which statement best explains this?
A. A small number of configurations have a large number of elements.
B. A small number of elements are arranged in a large number of configurations.
C. There are several elements in the human body that have not been discovered yet.
D. The human body does not need more than carbon, hydrogen, and oxygen to survive.
B. A small number of elements are arranged in a large number of configurations.
When scientists obtain new information, what happens to an existing scientific theory?
It is revaluated!
In 1897, Joseph Thomson discovered that atoms contained electrons. He proposed a change in the atomic theory of that time, and the theory was modified because of his discovery. Since Thomson’s discovery, atomic theory has been further modified.
What is the best explanation for why scientific theories are modified?
Scientific theories are modified because new evidence that supports a revision prompts scientist to modify the earlier theories.
Which of the following statements correctly describes the structure of an atom and its subatomic particles?
A. Atoms have a nucleus that contains electrons that are orbiting neutrons and protons that orbit the electrons
B. Atoms have a nucleus that contain electrons and neutrons; protons orbit around the nucleus
C. Atoms have a nucleus containing protons and neutrons; electrons surround the nucleus in a cloud
D. Atoms consist of protons, neutrons, and electrons that all orbit each other in a large mass
C. Atoms have a nucleus containing protons and neutrons; electrons surround the nucleus in a cloud
Scientific knowledge may change as new evidence or information is discovered. Which of the following would not be a result of new scientific research and information?
A. Binomial nomenclature is assigned to a recently identified plant species.
B. An endangered monkey species is put in a reserve for protection from extinction.
C. A newly discovered chemical element will be added to the periodic table of the elements.
D. A nonnative plant species will begin to reproduce rapidly after being introduced into a swamp ecosystem.
D. A nonnative plant species will begin to reproduce rapidly after being introduced into a swamp ecosystem.
How do scientific investigations differ from scientific experiments?
Scientific investigations involve observations and studying facts while scientific experiments involve an independent & dependent variable and the scientific method.
Scientists often make explanations about some aspect of the natural world when facts have been repeatedly confirmed through observations. What TERM refers to these explanations?
The vocabulary word THEORY
THEORY refers to explanations about some aspect of the natural world when facts have been repeatedly confirmed through observations.
The nucleus contains protons and ______.
neutrons
Elena discovered that Silicon (Si) is found in Group 14, Period 3 on the periodic table. Where should Mario look for another element that has similar properties?
A. in Group 14
B. in Period 3
C. on the opposite side of the periodic table
D. for any other element that begins with the letter N
A. in Group 14
Because elements in the same group share similar properties
They are all known for their contributions to the atomic theory.
Consider the work of scientists investigating a popularly held theory. As scientists continue to investigate this particular theory, they begin to find evidence that contradicts one of the main ideas proposed by this theory. Although many previous researchers have supported the theory, the latest research definitely indicates one area of the theory is completely wrong.
What should the researchers propose? Aka what do the researchers do????
They should propose modifications to the existing theories that take into account their new discoveries.
What type of substance is always made up of a single type of atom?
An ELEMENT is always made up of a singular type of atom.
In Science class, Sharon told his classmates that elements are like the letters of the alphabet. What did Sharon mean by this analogy?
A. Each element has a name.
B. Each element is represented by one or two letters.
C. There are the same number of elements as there are letters in the alphabet.
D. There is a finite number of letters that can be combined in different ways to make many words.
D. There is a finite number of letters that can be combined in different ways to make many words.
What is a theory?
Repeated observations that are supported by extensive evidence. Theories explains why natural phenomenas occur
Greek philosophers such as Democritus and Aristotle had ideas about the composition of matter. For example, Democritus believed matter was made of tiny, solid spheres that he called atomos, and Aristotle thought matter was made of earth, water, fire, and air. Aristotle's idea of matter was the accepted idea for over 2,000 years until John Dalton came up with a new theory about matter.
Which of the following best explains why Dalton’s theory became more widely-accepted over Aristotle's theory?
A. Aristotle’s theory did not have enough direct evidence due to poor observational tools.
B. Dalton’s theory was more complete because more respected scientists found the ideas possible.
C. Dalton’s theory had repeated observations which were supported by extensive evidence.
D. Aristotle’s theory became the law of conservation of mass when he documented phase changes of matter.
C. Dalton’s theory had repeated observations which were supported by extensive evidence.
What is the charge of the 3 subatomic particles?
Proton: positive charge
Neutron: neutral charge / no charge
Electron: negative charge
The periodic table of elements is organized into ______ and periods.