Unit 2 review ©
- Look at the models of the atom that have progressed over time, which scientist.
Thought it looked like a solid ball? ______
Thought it was a positive background with negative particles stuck in it? ______
Discovered the nucleus and thought the atom was mostly empty space? ______
Determined that electrons are arranged in specific energy fields? ______
Discovered the neutron? ______
What does the current model of the atom look like? ______
- What are the 3 particles an atom is made of? What is the electric charge of each? Mass of each?
- Look at the periodic table.
- For the element oxygen (O) find the: # of protons # of neutrons and # electrons for an electrically neutral atom.
# electrons ______
- Draw the Bohr diagramfor oxygen (if you don’t remember what a Bohr diagram is. Look back at the first question) (remember the 2-8-8 rule)
- If you added a neutron to this atom what would it be called? ______
- How would the atom become an oxygen ion? ______
- Is an oxygen ion positive or negative? Why? ______
- Could the atom have 9 protons and still be oxygen? Explain why or why not. ______
Sulfur has 3 isotopes. Use the periodic table to find the Isotopic mass and % abundance of Sulfur-33Isotopic Mass / % Abundance
Sulfur-32 / 31.972 / 94.93
Sulfur-33 / ??????????? / ??????????
Sulfur-34 / 33.967 / 4.29
- Look at the periodic table again.
- What are the all elements on the left of the zigzag line? ______
- What are the elements on the right? ______
- What are the elements that touch the line? ______
What are the general properties of metals?
What are the general properties of non-metals?
What are the general properties of the main families? Which elements belong in each?
What type of bonds are formed between metals and non-metals?______
What type of bonds are formed between non-metals and non-metals? ______
When sodium bonds ionically with chlorine 1 electron is transferred. Explain why. ______
What is an element? ______
What is a compound? ______
What is a mixture? ______
Which of the above can you separate by physical means? (filtering, using your hands, using magnet, etc…)
What is a solution? ______
What is a saturated solution? ______
What is an unsaturated solution? ______
What is the formula to calculate the concentration of a solution?
An experiment requires a total of 600 mL solution of methyl alcohol and water with a 45% concentration. What volume of methyl alcohol should be used?
Name the physical properties of substances.
Name the chemical properties of substances.
Water freezing is what type of change? Physical or chemical? Why? ______
Paper burning is what type of change? Physical or chemical Why? ______
What does a chemical change result in? ______
What does the law of conservation of mass say? ______
Balance the following:
Cl2 + NaBr ---> NaCl + Br2 H2 + N2 --- NH3
Na + Br2 ---NaBr CuCl2 + H2S --- CuS + HCl
What are the 4 states of matter? ______
In which do the molecules move the fastest? ______
What are the 6 phase changes? List which phase is changing to which for each.
Draw a phase change diagram for water: Label the phases and phase changes
What does density measure? ______
What is the formula for density? ______