8th Grade Advanced Science Midterm Study Guide Observing vs. Inferring Observations are ___________________ Inferences are _______________________ You can use your observations to make inferences. Observation: Maya is wearing a pink shirt, pink pants, and has a pink backpack. Inference: Maya likes the color pink. Inferences are based on observations. They are an explanation of your observations.

Mass, Volume, Length, Density Mass is measured with a ___________________ and the unit is ____________________ Volume can be measured with a ruler using the volume formula _________x________x_______ Or volume can be measured with a graduated cylinder. This is called _____________________ Final volume- initial volume = volume of the object. Density measures the amount of _______________ in a given ____________. The formula for density is _____________ divided by ______________. Or D= m/v

Mass vs. Weight Mass is not the same as _________________. Weight is the measure of how much __________________ is pulling down on you. Your weight can change if you move locations, but your ____________________ stays the same. Mass is a measure of how much ______________ is in an object.

Replication and Repetition: Replication is when another scientist copies your experiment to check for accuracy and look for mistakes. Repetition is sometimes called repeated trials. Repetition is when you _____________________ the experiment to look for mistakes and check for accuracy.

Scientific Experiments and Scientific Investigation Science experiments require you to actively test your hypothesis by doing an ______________________. A scientific investigation does not require an _____________________ instead you might do research, make a model, or just collect data through making observations with your five ___________________.

Steps of the Scientific Method

1. Identify the ____________________ (You usually write this in the form of a question)

2. Make _________________with your five senses and then use your observations to make an ______________________ that explains your observations.

3. Form a hypothesis. Your hypothesis is usually written as an “If ___________then___________because statement.”

4. Identify your __________________ (IV, DV, _____________ and __________)

5. Test your _________________ in an experiment or __________________

6. Collect _________________ by making observations.

7. Analyze your _________________ and create a model (usually a chart or _______________ of your data)

8. Draw a _____________________ that explains your results and tells if your hypothesis was supported or _____________.

8th Grade Advanced Science Midterm Study Guide Scientific Explanation (conclusion) Your conclusion explains your _________________ and tells if your hypothesis is supported or unsupported. What do you use as evidence in your conclusion?

Empirical evidence is _______________ or __________________ collected in an experiment or investigation. Empirical evidence is used to support or un support your hypothesis

Theory vs. Law Theories are ______________ Laws Theories must ____________________ why something happens. Ex) Theory of change over time explain why organisms adapt to be better suited to their surroundings. Laws do not ___________________. Laws tell what happened. Laws explain an observed _________________ in nature. Ex) Law of gravity says what goes up must come down. If you throw something into the air it will always __________________________________.

The Theory of the Atomic Model says: Everything is made up of _________________ and atoms make up __________________. Therefore, everything is made of ___________________. Atoms are the smallest unit of any _____________. Atoms are made of sub atomic particles called ______________, ______________, and ________________.

Theories can change! The atomic model ___________________ many times as we got new and better _________________. The current atomic model says that the nucleus is very small and ___________________. It also says that ________________ and __________________ are found in the nucleus. ___________________ are found in electron shells and they _____________________ around the nucleus. We know the protons have a ________________ charge. The electrons have a ________________ charge. And the neutrons are ______________, meaning they have no _________________. The current model states that the electrons move so fast we cannot see them and instead we call the moving electrons an electron ________________. The atomic model could change again if _____________________________.

Physical vs. Chemical Properties Physical properties are ______________________ of matter measured through ____________________. Physical properties of matter do not __________ or _______________bonds. Examples of physical properties are: color, texture, size, magnetism, density, malleability, mass, electrical and heat conductivity, and solubility. Physical properties allow us to compare and classify ____________________________. Chemical properties ________________ and _______________ bonds. Chemical properties will create a _____________ substance. Chemical properties are only observed when the substance undergoes a ___________________ change and becomes a new substance.

8th Grade Advanced Science Midterm Study Guide The four states of matter are: 1 2 3 4 In solids particles are __________________ packed and the volume and shape are ____________. Solids have a greater _______________ because the particles are tightly packed in a specific volume. In liquids the particles are _________________ tightly packed. In liquids particles can ___________ and this allows a liquids shape to ___________________. Liquids have a fixed _______________ but not a fixed shape. In gasses, the particles are _________________. The particles move quickly and spread ________________. Gasses have no fixed ________________ or __________________. Gasses are less d_________________ than solids. Plasma is an _______________________ gas. Plasma is when the elctrons contain so much ________________ they break free from the _________________ shell and move away. We find plasma in ________________________>

Elements: Elements are found on the ___________________ ______________________. Elements are pure substance because they only contain ________________ type of __________. Elements can _________________ to make molecules and compounds. The periodic table is organized into _____________ that are the vertical columns and periods that are _______________________ ____________________. Elements in the same group or ________________ share similar ___________________ including the number of valance ______________________. The periods of periodic table show how element properties repeat in a _____________________. ________________________ created the periodic table. The periodic table is organized by increasing atomic _________________. When you look at an element you will see the element name, symbol, atomic ___________ and atomic _____________________. The atomic number tells us the number of _________________ and _________________. The atomic mass – the atomic number tells us the ______________. Ex) oxygen has an atomic mass of 16 – 8 (the atomic #) = 8 neutrons

A Lewis dot structure tells you the number of _______________ ________________________. You draw one dot for each __________________. Lewis dot structures help us determine if elements will ______________________. Draw dot structures for

H F O

8th Grade Advanced Science Midterm Study Guide

Ionic bonds form between __________________

and ____________________________. Ionic bonds transfer _____________________. The metal is the ________________________ The metal is the ____________________ ion The nonmetal is the _____________________ The nonmetal is the ______________________ ion An ionic compound is _____________________ The signs or charges ______________________. Mg + F =

Covalent bonds do not form

_______________ Covalent bonds do not transfer electrons they _______________________. Covalent bonds produce __________________ compounds. In a covalent bonds the elements move so close together that the valance shells _________________________. The electrons in the overlap are shared as long as the atoms are together. When the electrons are shared each atom/element has a _______________ valance shell. Ex) Cl + Cl =

The law of conservation of mass says

1. Matter cannot be _______________ 2. Matter cannot be _______________ 3. Matter can be _________________ 4. When matter is transformed the physical

and chemical __________________ can change, but the ________________ must stay the same.

pH Scale The pH scale measures from ___________ to _____________ 0 - ________________ are acids pH of 7 is __________________ pH above 7 to 14 is __________________ Substances that are acidic release ____________ ions. Substances that are basic release _____________ ions.

Mixtures can be _________________ or

________________________. A homogenous mixture is sometimes called a ___________________. A solution is a ______________________. A heterogeneous mixture is called a mixture because it is not the ________________ throughout.

Solute: is what is being __________________ in a solution. Ex) koolaid powder Solvent: is what is doing the _________________ in a solution. Ex) water to dissolve the koolaid Solubility: is the amount of solute that can be ______________ by the solvent. Ex) The koolaid and water combined.

8th Grade Advanced Science Midterm Study Guide