Atoms and Elements

Atoms and Elements

6.5

Atoms

Atoms are the smallest unit of matter, which makes up everything (except energy!). There are smaller pieces that make up an atom called subatomic particles. They include protons, neutrons, and electrons.

Subatomic Particles

Protons are positively charged (+), Neutrons are neutrally charged (0), and electrons are negatively charged (-)

Multiple Choice

What is the smallest unit of matter?

• Atoms

• Electrons

• Energy

• Heat

Multiple Choice

Protons are--

• Negatively charged (-)

• Positively charged (+)

• Neutrally charged (0)

Multiple Choice

Electrons are--

• Negatively charged (-)

• Positively Charged (+)

• Neutrally charged (0)

Multiple Choice

Neutrons are--

• Negatively charged (-)

• Positively charged (+)

• Neutrally charged (0)

Subatomic particles

The nucleus is the center of the atom and contains the protons and neutrons. It has a positive charge. It has most of the mass of the atom and is super tiny compared to the overall atom. Fun fact: atoms are mostly empty space!

Subatomic Particles

Electrons are way tinier than protons or neutrons so they barely have mass. They DO NOT contribute to the mass of the atom. They exist in the electron cloud outside the nucleus.

Multiple Choice

What is the charge of the nucleus?

• Neutral

• Positive

• Negative

Multiple Choice

What is in the nucleus?

• Protons and electrons

• Electrons and neutrons

• Neutrons and protons

• Electrons and negatrons

Multiple Select

Which statements are true about atoms

• Most of the mass is located in the nucleus

• Electrons are larger than the nucleus

• The nucleus is much smaller than the nucleus

• The particles of an atom are close together

Multiple Choice

The size of protons in an atom must be

•  smaller than the atom but larger than the electrons

• smaller than the electrons but larger than the neutrons

• smaller than the neutrons but larger than the electrons

• smaller than the atom but larger than the neutrons

Elements

The number of protons determines what type of element an atom is. An element is made up of only one type of atom. The number of protons is also known as the atomic number. The atomic number is how elements are arranged on the periodic table.

Multiple Choice

A student receives a model of an atom that contains seven protons, neutrons, and electrons, and has an atomic mass of approximately 14. What procedure can the student use to identify the atom?

• The student can reference the periodic table and find the element that has an atomic number of 7, which represents the number of neutrons in the atom.

• The student can reference the periodic table and find the element that has an atomic number of 14, which represents the number of electrons and neutrons in the atom.

   

• The student can reference the periodic table and find the element that has an atomic number of 14, which represents the number of protons and neutrons in the atom.

• The student can reference the periodic table and find the element that has an atomic number of 7, which represents the number of protons in the atom.

Periodic table

Created by Dmitri Mendeleev, the periodic table organizes elements in order of their number of protons/their atomic number. The number of protons determines the properties of the element. The elements are grouped by similar properties on the periodic table.

Multiple Choice

The atomic number is based on--

• The number of neutrons

• The number of protons

• The number of electrons

• The number of negatrons

Multiple Choice

Fluorine has an atomic number of 9 and an atomic mass of 18.998.  How many protons does an atom of fluorine have?

• 18

• 19

• 9

• 8

Atoms

The number of electrons equals the number of protons unless otherwise stated.

The atomic mass = #protons + #neutrons

Multiple Choice

Sodium has 11 electrons and weighs 25. What's the atomic number?

• 11

• 25

• 14

• 44

Multiple Choice

The atomic number of Calcium is 20. It has 20 electrons. It weighs 42 amu. How many neutrons does it have?

• 42

• 20

• 22

• 15

Multiple Choice

The number of protons in Tungsten is 74. The number of electrons is 74. The atomic mass is 97. How many neutrons does Tungsten have?

• 74

• 23

• 12

• 97

Multiple Choice

The number of protons in lead is 82. It has 23 neutrons. What is its mass?

• 23

• 82

• 74

• 105

Atomic symbols

Multiple Choice

What is the atomic mass of copper?

• 29

• 63.546

• 25

• 21

Periodic Table

The periodic table is organized into metals, nonmetals, and metalloids.

Metals are shiny, highly conductive (they transfer heat and electricity well), and solid.

Periodic Table

Nonmetals are colored or colorless insulating gases that form compounds with one another. 

Between metals and nonmetals are metalloids, which have intermediate or mixed properties.

Multiple Choice

You found an object that is shiny, hard and conducts electricity and heat well

• Nonmetals

• Metalloids

• Metals

Bonds

Two or more atoms interact to form new substances, which are held together by electrical forces (bonds).

Two kinds of bonds: Ionic and covalent

Bonds

Ionic bonds are formed when one atom gives an electron to another atom. This is like having a bag of Takis and someone taking it.

Covalent bonds are formed when two or more atoms share electrons. This is like sharing your bag of Takis to someone else.

Ionic bonds occur between metals and nonmetals and covalent bonds occur between nonmetals

Multiple Choice

Ionic bonds--

• Form by sharing electrons

• Form by giving electrons

Multiple Choice

Covalent Bonds--

• Form by sharing electrons

• Form by giving electrons

Compounds and Mixtures

So we know what elements are, right? Compounds are two or more elements chemically combined in fixed ratios. They are pure substances because, like elements, they are consistent throughout. For example, water, H2O, is a compound

Compounds and Mixtures

Mixtures are combinations of compounds and elements and are not consistent throughout. They can be physically separated. This is NOT an example of a pure substance. Example of a mixture is air (which is made up of different gasses) or chex mix.

Subject | Subject

Some text here about the topic of discussion

Multiple Choice

What is an example of a mixture?

• Air

• Oxygen

• Table Salt

• Pure water

Multiple Choice

When you boil salt water, you evaporate the water and leave the salt behind. This makes salt water--

• A mixture

• A compound

Multiple Choice

An element is a--

• Pure substance

• Mixture

Multiple Choice

Compounds are--

• Pure substances

• Mixtures

Water

Water, or H₂O, is polar, which means that it's partially positive and partially negative.

The oxygen pulls on the electrons from the hydrogen, making it more negative. The hydrogens have the electrons pulled away from them, making them more negative.

Water's polarity

Multiple Choice

If sodium (Na) is positive, which part of water (H₂O) will it be attracted to?

• Hydrogen

• Oxygen