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Define science.
A system of knowledge and the methods you use to find that knowledge
Define matter.
The stuff that material things are made of.
What must occur for a process to be a chemical reaction?
A change in the chemical structure of the substance involved.
Define the kinetic theory.
The kinetic theory states that all particles are in constant motion.
what is the charge of the nucleus of every atom?
Positive.
Give an example of a case where the branches of natural science overlap.
The study of the stars is astronomy, but it also includes studying their chemical composition (chemistry) and how they orbit (physics).
What is a substance made up of only one type of atom called?
Element
What is the difference between a physical change and a chemical change?
A physical change does not alter the chemical composition of the substance. A chemical change changes the chemical composition (what the substance is made of).
How do gas particles cause pressure?
By moving around and bumping into things.
Which two particles can be found in the nucleus of an atom?
The protons and the neutrons.
What is the goal of the scientific method?
To objectively test ideas and gather data. Data can then be used to form conclusions about the world.
What type of substance is made up of more than one type of atom bonded in definite proportions?
Compound
Explain why a flame is not considered matter.
Flame is a chemical reaction. What is seen is the light given off by the reaction. It has no physical mass and is not matter.
What happens to the pressure of a gas when it is heated in a rigid container?
The pressure will increase.
What is the charge of an electron? A proton? A neutron?
Electron = -1
Proton = +1
Neutron = neutral
You perform an experiment and the resulting data do not support your hypothesis. What is the next step you might take?
Make a new hypothesis (modify the former one) and try the experiment again.
Run the experiment again and see if the results are the same.
Compare and contrast homogenous and heterogenous mixtures.
Both have multiple substances mixed together without being chemically combined. Homogenous mixtures look the same, so you can't see the different things mixed together. Heterogenous mixtures look different, so you can see at least some of the different things in them.
Explain why a saltwater solution is considered a homogeneous mixture and not a pure substance.
altwater is a mixture because it involves salt dissolving in water. The salt does not combine with the water molecules. The mixture is homogenous because it looks the same.
What happens to the volume of a gas in a balloon when it is heated?
The volume will increase.
What did Thomson add to the model of an atom? Rutherford? Bohr?
Thomson determined that atoms are made of small particles, discovering the electron. Rutherford stated that atoms have a positively-charged nucleus and that electrons move around the nucleus. Bohr stated that electrons orbited the nucleus in fixed distances.
What are the SI units for length, mass, and temperature?
Meter, gram, Kelvin
Define physical property and give three examples.
A characteristic of a material that can be observed or measured without changing the chemical composition of the material. Examples: color, density, size.
At room temperature (25℃), a substance with a melting point of 35℃ would be a … (solid, liquid or gas?)
Solid
What happens to the pressure in a rigid container if more gas is added?
The pressure increases.
Compare atomic number and mass number.
The atomic number is the number of protons in an atom and is specific to each element. The mass number is the number of protons plus the number of neutrons within a single atom. The mass number can be different for atoms of the same element.