Notes

REVIEWER
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scientific method
observation = analysis
explanation = hypothesis + experiment = observation >theory(Analysis | observation ... observation hypothesis + experiment>observation -> Laws

General steps for solving problems include:

Defining the problem
Proposing possible solutions
Solving the problem

The scientific method is a procedure for processing information in which we:

Collect the facts
Formulate a hypothesis
Plan and do experiments
Modify the hypothesis if necessary
General steps for solving problems include:
Defining the problem
Proposing possible solutions
Solving the problem



Hypothesis: A hypothesis is indeed based on initial observations or educated guesses. It serves as a testable proposition to explain a phenomenon and is subject to further investigation and experimentation. Hypotheses are not considered proven until they have been rigorously tested and supported by evidence.

Theory: A scientific theory is built on a substantial body of evidence and experimentation. It explains and integrates a wide range of phenomena and observations. While theories are robust and well-supported, they are not considered absolute truths and can evolve or be refined in response to new evidence. Theories are subject to ongoing debate and scrutiny within the scientific community.

Law: Scientific laws describe fundamental, concise relationships or principles that are widely accepted as being accurate and universally applicable under specific conditions. Laws are typically based on extensive empirical evidence and are considered to be highly reliable. They are not typically subject to revision or debate to the same extent as theories.


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A phase is a homogeneous part of a system separated from other parts by physical boundaries. A system is simply the body of matter under consideration.

Defining the problem
Proposing possible solutions
Solving the problem


^pure = elements and compounds elements =cannot be chemically interconverted or broken down into simpler substances
compounds = 2 or more elements chemically bonded
MIXTURES= 2 or more different elements not chemically bonded

-hetero seen and not uniform
-homo not seen uniform
Naked eye and genous

physical change - melting, and cutting are examples no chemical use ( physical properties no chemical properties)
chemical change - It refers to the transformation of one or more substances into different substances, like through combustion or burning (chemical properties use of chemical change) - physical properties describe how a substance behaves without changing its chemical composition, while chemical properties describe how a substance interacts with other substances to form new substances.)

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Element names: Many are derived from early Greek, Latin, or German words that describe some property of the element. For example, iodine is taken from the Greek word iodes, meaning “violetlike,” and iodine is certainly violet in the vapor state. Some elements are named for the location of their discovery—for example, germanium, discovered in 1886 by a German chemist. Others are named in commemoration of famous scientists, such as einsteinium and curium, named for Albert Einstein and Marie Curie, respectively.

Most historical names can be referred to on their symbols like Sodium = Natrium and Gold = Aurum most elements and in um as well on their historical names

Most substances can be decomposed into two or more simpler substances. It is rare to find elements in nature in pure form- either compound or mixture... ( Alkali, Alkalane, Transition metals, halogens, noble gases) Oxygen is indeed one of the most abundant element on Earth, next is silicon in human bodies as well oxygen is the most present element or substance.

Metals - Good conductor of heat positive ions
Nonmetals- Neagative ions poor conductor of heat
metalloids- can have traits of metals and non metals

basically what metal is is almost the exact opposite of what nonmetal is as metal is lustrous, malleable and good conductor of heat nonmetals are opposite...

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An ion is a positively or negatively charged atom or group of atoms. An ionic compound is held together by attractive forces that exist between positively and negatively charged ions. A positively charged ion is called a cation (pronounced cat-eye-on); a negatively charged ion is called an anion (pronounced an-eye-on).


physical and chemical properties can help us among many others, help us characterize and identify elements

Energy is the capacity of matter to do work.
Potential Energy: Potential energy is energy that is stored within an object and has the potential to do work in the future. It arises from the position, configuration, or state of an object. In your example of archery, when you pull back the bowstring, you are doing work to store potential energy in the bow. The potential energy is then released when you let go of the bowstring, and it is converted into kinetic energy as the arrow accelerates and moves through the air.

Kinetic Energy: Kinetic energy is the energy of an object in motion. It is associated with the velocity and mass of an object. When an object is in motion, it has the ability to do work because of its speed and mass. In your example of body movement, when you move your body, it possesses kinetic energy because it is in motion. This kinetic energy can be used to perform various tasks or activities.


expressing heat energy through joules and calorie :
formula
1 kj = 1000 j
and 1 kcal = 1000 cal