Elements and Compounds

Multiple Choice

Which of the following is the simplest form of substance?

• solution

• compound

• element

• mixture

Multiple Choice

Which of the following statements describes an element?

• It contains only one kind of atom.

• It can be decomposed by ordinary chemical means.

• It is composed of atoms of two or more elements that bond together.

• It has unique properties that are different from the properties of its individual elements.

Multiple Choice

Which of the following statements describes a compound?

• It contains only one kind of atom.

• It can be separated by physical means.

• It cannot be decomposed into simpler types of substances.

• It consists of atoms of two or more different elements bond together.

Multiple Choice

Which statement correctly explains the relationship between molecules and compounds

• Both are made of 2 different atoms chemically combined

• Both are made of at least 2 atoms, but compounds are 2 different atoms.

• Molecules are made of one atom, compounds are made of 2 atoms

• Both are made of at least 2 atoms, but molecules are 2 different atoms.

Multiple Select

Select all of the vocabulary words that describe oxygen gas (O₂).

• Molecule

• Compound

• Element

• Mixture

Multiple Select

Select all of the vocabulary words that describe water gas (H₂O).

• Molecule

• Compound

• Element

• Mixture

Multiple Choice

Compounds are two or more elements that are chemically bonded together.

• True
• False

Multiple Choice

Which of the following is a chemical compound?

• Co
•  CO₂
• Mg
• Al

Multiple Choice

A compound is represented by a:

• Heart
• Atomic Mass
• Atomic Number
• Formula

Multiple Choice

What elements made up the compound Carbon dioxide?

• Carbon and Oxide

• Carbon and Oxygen

• Carbon and Hydrogen

• Carbon and Carbon

In this example, each molecule of water (a compound) has 2 hydrogens (subscript 2) and one oxygen atom (we do not write the subscript 1). The coefficient is 2 or 5. This tells us how many molecules of water we have.

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We Count the number atoms using subscripts and coefficients.

Multiple Choice

Which of the following correctly identifies the subscripts and coefficients for the chemical formula?

• Coefficients: 3, 4

  Subscripts: 4

• Coefficients: 4

  Subscripts: 3, 4

• Coefficients: 3, 4

  Subscripts: 3, 4

• Coefficients: 3

  Subscripts: 3, 4

Multiple Choice

Challenge: How many total atoms are there in one molecule of aluminum sulfate?

• 17

• 8

• 9

• 21

C-1
H-4
O-1

How many of each element?

6 + 12 + 6 = 24

How many atoms total?

C₈N₄H₁₀O₂

What is the chemical formula for caffeine?

Multiple Choice

How many atoms of Oxygen are in a molecule of Sucrose?

• 12

• 22

• 11

• 10

Multiple Choice

How many hydrogen atoms would be in 2 molecules of Sucrose? (There will be twice as many as there are in 1 molecule)

• 24

• 22

• 44

• 20

Multiple Choice

How many sulfur atoms are there in 2 molecules of aluminum sulfate?

• 4

• 2

• 6

• 12

• Matter is not created or destroyed in a reaction.

• This is why we learn to count atoms in a compound.

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Law of conservation of mass

Let's MIX things up a bit!

• Mixture is not uniform.

• Can see individual components

• Salads, Vinegarettes,

​​Heterogeneous mixtures

• The mixture is uniform.

• Cannot pick out individual components.

• Solutions and alloys

Homogeneous Mixture

Multiple Choice

Which of the following would be considered a homogeneous mixture?

• Salad dressing

• Salt water

• Cereal with milk

• Oatmeal

• Mixtures can be separated by physical means.

• No chemical reaction is necessary to separate mixtures.

• Separating a compound requires a chemical reaction!

Multiple Choice

Which method should be used to separate a mixture of salt and water?

• Manual separation

• Boiling

• Filtration

• magnetatism

Why do chemical reaction occur?

• When we perform chemical reactions, we are taking advantage of a substances instability, producing new products.

Multiple Choice

Another term for being chemically inactive is...

• Inert
• Inbert
• Insert
• Inmert