MATTER UNIT QUESTIONS
- Classify the following substances as either an element or a compound.
a. sulfurb. uraniumc. H2Od. calcium
e.sodium chloridef. heliumg. alcoholh. iron (III) oxide
2. Is salt water a substance? Is sodium chloride? Why or why not?
3. Classify the following as either an element, a compound, a homogeneous mixture, or a
heterogeneous mixture.
a. your textbooke. magnesium chloride
b. a carf. ink in a pen
c. nitrogeng. chromium
d. rust (iron oxide)
4. What is the mass of 5.0 kg of mercury when it is transferred to a planet having twice the
gravity?
- Technician A and technician B are examining the same substance. Technician A records the
mass, volume, and weight of the substance and decides that it is sugar. Technician B records
the melting point, boiling point and density of the substance and decides it is sodium chloride.
Which technician’s answer is most likely correct? Why?
6. Two vials containing colorless liquids are placed on a balance. Their combined mass is
recorded as 98.25 grams. The contents of one vial is poured into the other and a white solid is
formed. When the two vials and their contents are reweighed will the reading be less than,
greater than, or equal to 98.25 grams? Explain.
- Consider two substances, A and B. The density of substance A is less than the density of substance B. Samples of substances A and B are put in two different containers and have the same volume. Which substance has the greater mass? Why?
- A chain bracelet is found. It looks like it may be made of either copper or gold. When the bracelet is put in water, the volume rises from 12.5 cm3 to 17.5 cm3. The bracelet has a mass of 45.0 g. Is the bracelet more likely to be made of copper or gold? Explain and show your work.
- Classify each of the following as a chemical change or a physical change. Explain.
a. A test tube of green cupric carbonate is heated. After heating the material in the test tube
is black.
- A match is burned.
- An ice cube is heated, it melts, and then turns to steam.
- A container of hydrogen gas is mixed with oxygen gas and allowed to sit overnight. In the morning the mixture containing hydrogen and oxygen will no longer burn.
- Compare and contrast a bronze and copper.
- You have a mixture of salt, sand, and iron filings that must be separated by using only physical changes. Describe what you would do to prepare samples of the three parts in separate dry containers. Explain why this process works.
- Why would it be necessary to include spaces between metal beams that are placed end to end
when constructing a bridge?
- Compare and contrast liquids and gases.
Extra Credit
(a)Lead has a density of 11.35 g/cm3 at 200C. Assume it is a solid in sheets 4.50 cm thick and 120.0 cm wide. What length of a sheet of lead at 200C must you buy to have a mass of 50.0 kg? Show all your work and follow significant figure rules in all calculations.
(b)A sample of gas at 150C (at 1 atm) has a volume of 2.58 L. The temperature is then raised to 380C (at 1 atm).
(i)Does the volume increase, decrease, or stay the same. Explain in terms of what is happening to the gas particles.
(ii)Calculate the new volume.