Elements
What is an element?
What is the center of an atom called?
Nucleus
Can elements, compounds, or mixtures be separated? And if they can be separated, tell how (physical or chemical means).
Elements- cannot be separated
Compounds- chemical means
Mixtures- physical means
A substance made of 2 or more elements that are chemically combined in a set ratio
What is a mixture?
A combination of two or more substances that are not chemically combined and can be separated.
Name 3 different elements.
Various answers (hydrogen, oxygen, calcium, gold, silver, etc.)
What is the basic particle from which all elements are made?
An atom
The formula for ammonia is NH3. How many atoms of each element are there? (Make sure to name the elements)
Nitrogen-1
Hydrogen-3
How many different atoms are there in a compound?
2 or more
Heterogeneous and homogeneous
Each element can be identified by its specific physical and chemical properties. What are at least 2 physical properties of copper?
A molecule is the smallest complete unit of what? Element, Compound, or Mixture
Compound
What shows the elements and ratio of atoms in a compound?
Chemical formula
What is the chemical formula for water?
H2O
Give three examples of a heterogeneous mixture.
Various answers: guacamole, salad dressing, salad, pizza, chicken noodle soup, etc.
Name at least 2 elements that only occur naturally as molecules.
Oxygen, Hydrogen, Fluorine, Chlorine, Nitrogen, Iodine, and Bromine
What is a molecule?
A group of 2 or more atoms held together by chemical bonds
Which of the following substances can be separated into simpler means: sodium, salt water, water, gold.
Water
Name three compounds and give the chemical formula for each.
Give three examples of a homogeneous mixture.
Various answers: honey, soy sauce, air, Kool-Aid, sweet tea, coffee
Which element makes up the majority of our atmosphere?
Nitrogen
What is the force of attraction between 2 atoms?
A chemical bond
A light green powder is heated in a test tube. A gas is given off, while the solid becomes black. In what classification of matter does the green powder belong? Be ready to explain.
Compound-the change in colour and formation of gas imply that a chemical change took place
What is the different between organic and inorganic compounds?
Organic compounds contain carbon and are usually bonded to hydrogen. Inorganic compounds usually don't contain carbon.
Name the four different methods that you can use to separate a mixture.