Term | Definition |
Atoms | The smallest parts of an element that retains the chemical properties of an element. |
Matter | Anything that takes up space is composed of matter including atom and molecules. |
Elements | A type of pure substance that can't be changed into a simpler substance. It is also only made up of one type of atom. |
Protons | Positively charged molecules located in an atoms nucleus. |
Electrons | Negatively charged particles that orbit around the nucleus. |
Democritus | The first person to come up with the idea of atoms and to state that atoms are indivisible. He also said that dividing an object a multiple times will eventually lead you to an atom. |
Dalton | He proved Democritus's theory and he also added that atoms are to small to be seen with the naked eye. |
Rutherford | He used the gold foil experiment and found that atoms had a nucleus. |
Thompson | He was the scientist who came up with the plum pudding experiment to prove that electrons are negatively charged. |
Bohr | He stated that electrons orbited around the atoms nucleus. He also created the correct model of the atom. |
Compound | A type of substance that is composed of two or more elements that are chemically combined. It is only able to turn into a simpler substance by a chemical change. |
Mixture | A substance that is composed of two or more different physically combined and they keep there own physical properties. |
Heterogeneous Mixture | A mixture that is not the same throughout the mixture and the components of the mixture can be distinguished with the naked eye. |
Homogeneous Mixture | A mixture that retains the same physical properties throughout the mixture and can't be visually distinguished with the naked eye. |
Physical Properties | A property that can be studied and observed without changing the matter being studied. |
Color | (Physical Property) The color of a pigment in a substance. |
Density | (Physical Property) The property that describes the relationship between an objects mass and its volume. |
Melting Point | The temperature at which a pure substance melts. |
Boiling Point | The temperature at which a pure substance boils. |
Chemical Properties | Properties that can only be noticed when they undergo a change in chemical composition. |
Ability to Burn | A chemical process that involves an object or substance reacting quickly to oxygen and producing light and heat. |
Ability to Rust | A chemical process that involves an object or substance reacting slowly with oxygen. |
Physical Changes | When a substance changes from one state of matter to another and the composition of the object has not changed. |
Changes in State of Matter | When a substance changes from one state of matter to another. |
Changes in Size or Shape | When a substance changes from one size or shape to anothe |
Chemical Changes | The result of the formation of one or more new substances with new physical and chemical properties. |
Color Change | A chemical change in which a substance changes color the chemical making of a substance might have changed. |
Temperature Change | When a substance is combined with another substance there might be an increase or decrease in temperature. |
Formation of a Precipitate | A chemical change in which two substances are combined and a solid or a precipitate is formed. |
Formation of a Gas | A chemical change in which solids or liquids are combined they might form gas bubbles. |
Period | A horizontal row on the periodic table. |
Atomic Number | The atomic number represents the number of electrons and protons. Elements are arranged numerically by atomic number on the periodic table. |
How to find the amount of neutrons | Round the atomic weight to the nearest whole number. Subtract the atomic number from the rounded atomic weight. |
Families | Families are groups with similar properties. |
Groups | Columns on the periodic table. |
Properties of Metals | Luster- having shiny surface
Conductors -heat and electricity to flow through them easily
Malleable- the ability to be hammered into different shapes
Ductile- the ability to be pulled into a wire like shape
High Density- heavy for its size |
Properties of Non-Metals | Brittle- breaks easily
Nonconductors- heat and electricity do not flow through them easily
Dull- it lacks luster |
Metalloids | Elements that have the properties of metals and non-metals
The metalloids are Boron, Silicon, Germanium, Arsenic, Tellurium, Polonium |
Chemical Symbols | They show the atoms of the elements composing a substance. Th first letter is always capitalized. No elements has the same symbol. |
Subscript | They show the number of each kind of atom in the compound. |
Covalent Bonds | A bond that contains two nonmetallic atoms. |
Ionic Bonds | A bond that contains one metallic atom and one nonmetallic atom. |
Law of Conservation of Matter | It states that the amount of matter doesn’t change during a chemical reaction the order is just rearranged. Another interpretation of the law is that matter can neither be created nor destroyed, but can be changed in form. |
Yield | The arrow that is used to distinguish between the reactants and products in an equation. |
Reactant | Substances that are broken apart or combined in a chemical reaction. |
Product | New substances that are formed in the chemical reaction. |
Coefficient | The number that comes before the chemical formula and shows the number of particles that participate in the reaction. |
Acids | An acid is something that falls between 1-6 on the pH scale. |
pH Scale | The pH scale is a tool that is used to measure how acidic or basic a solution is. |
Base | A base is a solution that falls between 8 and 14 on the pH scale. |
Neutral Solution | A neutral solution is not an acid or a base because on the pH scale it falls on 7. |
Atoms have _____,________, and _______ | protons neutrons electrons |
The______ of the atom is located in the_____ with electrons moving in random patterns in the space around the nucleus. | nucleus center |
_______ can be separated by physical means such as filtration, sifting, or evaporation. | Mixtures |
_______ can only be made into simpler substances (elements) by chemical changes. | Compounds |
____ have a sour taste | Acids |
_____have a bitter taste | Bases |
If the indicator __________ turns a milky white when added to a substance, the substance is an acid. | phenolphthalein |
If the indicator phenolphthalein turns a ________when added to a substance, the substance is a neutral solution. | light pink |
If the indicator phenolphthalein turns a dark pink when added to a substance, the substance is ________. | Bsae |
_______ strips will turn varying shades of color ranging from a dark red to represent zero and a dark blue to represent 14. | pH |
Blue litmus paper turns red when the solution is an _____. | Acid |
____________ turns blue when the solution is a base. | Red litmus paper |
____________ are located on the right side of the yield sign. | products |
___________ are located on the left side of the yield sign | reactants |
If no subscript is shown then that means there is only ____ of that element | one |
The boiling point of pure water is ______°F or 100°C. | 212 |
The melting point of pure ice is ________°F or 0°C. | 32 |