Name: _________________________________
Period__________________
7th Grade Chemistry Benchmark Practice
Density
1. Calculate the volume of a liquid with a density of 2.8 g/mL and a mass of 35 g.
2. When 30 mL of water is added to a graduated cylinder, the graduated cylinder has a
mass of 120 g. If a stone is added to the graduated cylinder, the water level rises to 35
mL and the total mass is now 126 g. What is the density of the stone?
Particles
3. Identify the phase transition and then whether heat is absorbed or released in each of the following.
Type of phase change
Phase Transition
Freezing
Melting
Vaporization
Evaporation
Sublimation
Condensation
Deposition
Liquid to Solid
Heat change (absorbed
or released)
Temperature of
Phase Change for
Water (°C)
Not Applicable
Not Applicable
The illustrations below represent molecules of three phases of matter.
A
B
C
4. Which diagram below represents the phase of matter with the most energy? _________
5. Which diagram below represents the phase of matter with the least energy? _________
6. If heat is added to the particles in diagram A, what phase will result? ________________
7. At what temperature does pure water boil? _____________________
8. At what temperature does pure water freeze? _____________________
9. Which phase of matter will expand the most when heated? _______________
10. Label the
Diagram with
the states of
matter and
applicable
phase
changes.
11. Is the
substance
gaining or
losing
energy?
12. What phase
change is taking place at the 90 minute mark? ________________________
13. What is the freezing point of this substance? ___________________
14. What is the boiling point of this substance? _____________________
15. Which of the following combinations would increase the solubility of a solid in liquid?
a.
b.
c.
d.
decrease the pressure and decrease the temperature
decrease the pressure and increase the temperature
increase the pressure and decrease the temperature
increase the pressure and increase the temperature
16. Which of the following combinations would increase the solubility of a gas in liquid?
e.
f.
g.
h.
decrease the pressure and decrease the temperature
decrease the pressure and increase the temperature
increase the pressure and decrease the temperature
increase the pressure and increase the temperature
17. Heating up water will help all of the following dissolve except ___________.
a. Helium
b. Salt
c. Salt
d. Copper sulfate
Use the graph of solubilities to
answer the following questions.
18. Which of the substances has
the highest solubility at
50°C?
____________________
19. How much potassium iodide
will dissolve at 30°C?
____________________
20. How many grams of sodium
nitrate will dissolve at 60°C?
____________________
21. At what temperature do
potassium nitrate and
sodium nitrate have the
same solubility? ____________
22. If a saturated solution of
potassium chlorate at
80°C?is cooled to 45°C, how
much precipitate will form?
___________________
23. What is the solubility of NH4Cl in 100g of water at 75 degrees C?
24. How much precipitate will form if a saturated solution of HCl at 25°C is heated to 70°C?
25. What phase of matter is NH4Cl most likely?
26. What phase of matter is HCl most likely?
27. Identify the type and quantity of atoms in each of the following
a. 3V2O5 ______________________________________________________________________________
b. 3NaHCO3
______________________________________________________________________________
c. 12NaBr
______________________________________________________________________________
d. 4K2CO3
______________________________________________________________________________
e. 2Sr3(PO4)2 ______________________________________________________________________________
What’s Missing?
28. ____________ + AgNO3 + Cu  Cu(NO3)2 + Ag
29. 2NaF + Br2  2NaBr + _________
30. CH4 + ____ O2  ____ CO2 + __________