7 - Unit 1, Section 1 - Day 2

Atoms, Elements, and Compounds: A Review

Unit 1, Section 1

Multiple Choice

The __________ __________ is the number of protons in the atom of an element.

• Atomic Number

• Mass Number

Multiple Choice

The mass number is the number of protons plus the number of __________ in the atom of an element.

• Neutrons

• Electrons

Atoms form bonds with other atoms to form chemical compounds

• Chemical Bond - a force that holds two atoms together

• Different elements can have a different number of chemical bonds

Chemical Bonds

Elements and Chemical Bonds

​Element	Number of Bonds​
​H	1​
C​	4​
O​	2​
N​	3​

A mixture is a combination of two or more chemical compounds

• Salt (NaCl) and water (H₂O) is an example

• Mixtures can be either:

  • Homogeneous

  • Heterogeneous

Mixtures

Homogeneous mixture - a mixture with only one phase

• Everything is mixed so thoroughly that you can't see the individual compounds

• "It all looks the same"

Homogeneous Mixtures

Hetereogeneous mixture - a mixture with multiple phases

• You can see the different compounds in a heterogeneous mixture

Heterogeneous Mixture

Multiple Choice

Kool-Aid (without ice) is an example of:

• A homogeneous mixture.

• A heterogeneous mixture.

Multiple Choice

Sweet tea with ice and lemon is an example of:

• A homogeneous mixture.

• A heterogeneous mixture.

Multiple Choice

Carbon forms _____ bonds in chemical compounds.

• 1

• 2

• 3

• 4