Atoms/Elements/Pure Substance/Mixtures Test

the smallest unit of an element that maintains the properties of that element

atom

a substance that cannot be separated or broken down into simpler substances by chemical means

element

a group of atoms that are held together by chemical forces

molecule

A substance made up of atoms of two or more different elements joined by chemical bonds

compound

A combination of two or more substances that are not chemically combined

mixture

describes something that does not have a uniform structure or composition throughout with parts that are easily seen

heterogeneous

describes something that has a uniform structure or composition throughout with parts that are not seen easily

homogeneous

A place to find information about elements.

Periodic Table of Elements

The most abundant elements found in living things.

hydrogen & carbon

The most abundant elements found in the Earth's crust.

oxygen & silicon

The most abundant elements found in the Earth's oceans.

hydrogen & oxygen

The most abundant elements found in the Earth's atmosphere.

oxygen & nitrogen

Examples of homogeneous mixtures

air, brass, & Kool-Aid

Examples of heterogeneous mixtures

pizza, salad, & tacos

Examples of compounds

sugar, water, & salt

Types of homogeneous mixtures

Solution

Types of heterogeneous mixtures

Suspension & Colloid

made up of more than one type of particle & can be separated by physical changes

Characteristics of Mixtures

regulate chemical activities of the body and build and repair body structures

proteins

contain genetic information and help the body build proteins

Nucleic Acids

used as a source of energy

Carbohydrates

store access energy and make up cell membranes

lipids

What are substances that contain hydrogen and carbon called?

organic

What is determined when blue litmus paper turns red?

presence of an acid

What is determined when red litmus paper turns blue?

presence of a base

What is determined when neither red or blue litmus paper changes color?

presence of a neutral

pH value of an acid

less than 7

pH value of a base

more than 7

pH value of a neutral

7

Ways that compounds are classified:

pH, organic or inorganic, role in the body

made up of one type of particle and cannot be formed or broken down by physical changes

Characteristics of Pure Substances

Classes of Matter

elements, compounds, & mixtures

What elements are in a molecule of sugar?

Carbon, Hydrogen, & Oxygen

How many atoms of hydrogen are in a molecule of sugar?

12

Neutrons present in Lithium if the atom had a mass number of 7

4

Protons and Electrons present in Lithium

3

Classes of Elements

metals, nonmetals, & metalloids

Positive particle found in an atom

proton

Negative particle found in an atom

electron

particle with no charge found in an atom

neutron

center of an atom that contains protons and neutrons

nucleus

outside region of an atom that contains the electrons

electron cloud

Why are atoms electrically neutral?

positive protons balance out the negative electrons

malleable, shiny, good conductors of heat and electricity, found left of the zigzag line

Metals

brittle, dull, poor conductors of heat and electricity, found right of the zigzag line

Nonmetals

semiconductors of heat and electricity, found on the zigzag line

Metalloids

How are all elements different from one another?

number of protons

What do protons and electrons have that neutrons do not?

charge

An abbreviation that represents an element, that is usually 1 or 2 letters long, with only the first letter capitalized, that contains letters from the elements name, but could come from different languages

chemical symbol

What tells you the number of protons in the nucleus of an element?

atomic number

Thought of the idea of the atom.

Greeks

Combined the ideas of elements and atoms together and created the Marble Model.

John Dalton

First to do the Cathode Ray Tube Experiment.

William Crookes

Used a magnet to discover electrons and used the Chocolate Chip Cookie Model.

JJ Thomson

Conducted the Gold Foil Experiment and discovered the nucleus.

Ernest Rutherford

How were the particles in the CRT explained not to be light?

The particles were attracted to the magnet, and light is not.

What happened in the Gold Foil Experiment that led to the discovery of the nucleus?

Alpha particles bounced back

What makes up most of the atom?

Empty Space

Who thought electrons moved in predictable orbits around the nucleus

Neils Bohr

How do electrons move?

Unpredictably like waves

Atoms of the same element that have a different number of neutrons.

Isotope

The number of protons plus the number of neutrons in an atom.

Mass Number

John Dalton's Atomic Theory

Matter is Made up of atoms.
Atoms cannot be divided into smaller pieces.
All atoms of an element are exactly alike.
Different Atoms are made up of different kinds of atoms.

What led to the neutron being discovered and added to the model of the atom?

The mass of the atom was not the same as the mass of the protons.

Where are electrons found and why?

electrons will be found closer to the nucleus because opposite charges attract.

Information known about a compound by looking at the formula

The elements that make it up and
The number of atoms for each type of element.