WorksheetsChemistry Pre/Post-Assessment
Total questions: 25
Worksheet time: 25mins
Name
Class
Date
1.
Hollywood is 2,215.2 miles away from Covington, Ga. Express this number in scientific notation:
a)
22152 x10-1
b)
2.2152 x103
c)
2.2152 x104
d)
0.2152 x10-4
2.
a)
Used to measure solids in lab
b)
Used to fasten objects together
c)
Used to light a burner
d)
Used to hold a test tube
3.
Use this model to explain fluorine's chemical properties
a)
Fluorine is non-reactive because its inner electron shell is full
b)
Fluorine has metallic properties because it has electrons to donate
c)
Fluorine is a gas because its outer electron shell is not full
d)
Fluorine is highly reactive because it needs one more electron to become stable
4.
Most parts of Dalton's Theory are accepted today. Give a limitation of his theory
a)
Atoms are not indivisible. They can be divided into protons, neutrons, electrons.
b)
Atoms of different elements are not different. All atoms are the same.
c)
Atoms of the same element are not similar to each other.
d)
Mass is not conserved in chemical reactions.
5.
Which part of an atom defines an element's identity?
a)
Electron
b)
Nucleus
c)
Proton
d)
Neutron
6.
What is the difference between a cation and anion?
a)
Cations are negative and anions are positive
b)
Cations are formed by gaining electrons, anions are formed by losing electrons
c)
Cation and anion mean the same thing
d)
Most metals form cations, while nonmetals form anions
7.
Why does atomic radius decrease across a period?
a)
Neutron number decreases across periods
b)
Proton and electron number decreases across periods
c)
As we move across a period, atoms spin faster, making them smaller
d)
Proton number increases across periods, causing a stronger pull on electrons
8.
Name Ca3(PO4)2
a)
Calcium phosphate
b)
Calcium phosphorus oxide
c)
Calcium(III) phosphide
d)
Tricalcium diphosphate
9.
Why does sugar (C12H22O11) melt at a lower temperature than salt (NaCl)?
a)
Sugar's ionic bonds are stronger than salt's covalent bonds
b)
Salt's ionic bonds are stronger than sugar's covalent bonds
c)
Sugar contains more atoms, making it less stable than salt
d)
Sugar's ionic bonds are weaker than salt's covalent bonds
10.
What can be changed to balance:
CH4 + Cl2 → CCl4 + HCl
CH4 + Cl2 → CCl4 + HCl
a)
Subscripts
b)
Coefficients
c)
Element identities
d)
Chemical formulas
11.
Which shows a balanced synthesis reaction?
a)
2Na + Cl2 → 2NaCl
b)
C + S8 → CS2
c)
C6H14 + O2 → CO2 + H20
d)
2H2O → 2H2 + O2
12.
What is the significance of 6.022 x1023?
a)
It is the distance from Earth to the moon in meters
b)
It gives the quantity of atoms or molecules in a mole
c)
It is the mass of 1 atom of Carbon-12
d)
It is the mass of a proton or neutron in grams
13.
9.01g of water (H2O) contains 1.01g hydrogen and 8.00g oxygen. What is the percentage of hydrogen in water?
a)
12.6% hydrogen
b)
1.01% hydrogen
c)
11.2% hydrogen
d)
22.4% hydrogen
14.
1 mile = 1609 m
If Darius ran 440 meters, how many miles did he run?
If Darius ran 440 meters, how many miles did he run?
a)
0.27 mile
b)
707,960 miles
c)
3.7 miles
d)
2049 miles
15.
Hannah's mass is 90720 g.
Express Hannah's mass in kg.
Express Hannah's mass in kg.
a)
90720000 kg
b)
90.72 kg
c)
0.09072 kg
d)
9.072 kg
16.
A _____ reactant is used up first and controls the quantity of product formed in a chemical reaction
a)
limiting
b)
excess
c)
theoretical
d)
stoichiometric
17.
Give a valid conclusion based on this heating curve
a)
Energy input is not required for melting ice
b)
Water temperature increases during vaporization
c)
Vaporization of water requires more energy than melting of ice
d)
Ice always melts the moment heat is added
18.
What occurs at the molecular level as water vaporizes?
a)
Water molecules increase in kinetic energy as they move faster
b)
Water molecules decrease in kinetic energy as they move slower
c)
Water molecules increase in potential energy as they move farther apart
d)
Water molecules decrease in potential energy as they move closer together
19.
Why is standard temperature and pressure important when dealing with gases?
a)
The volume of a gas changes with temperature and pressure
b)
The molarity of a gas changes with temperature and pressure
c)
Scientists define laws for every situation
d)
The pressure of a gas changes with temperature
20.
Boyle's Law: at a fixed temperature, pressure and volume of a gas are inversely proportional.
For example...
For example...
a)
If you put a balloon in the freezer, it will shrink.
b)
Friction with the road causes tire pressure to increase as you drive.
c)
When forced into a smaller container, gas pressure increases.
d)
When pressure decreases as a diver surfaces, gases in their body decrease in volume.
21.
Which factor does NOT affect the rate a solid dissolves into a solution?
a)
Temperature
b)
Pressure
c)
Agitation
d)
Surface area of solute
22.
Which variable affects the freezing point of a solution?
a)
The quantity of the solution
b)
The moles of solution
c)
The mass of a solution
d)
The amount of solute in a solution
23.
In acid-base neutralization
a)
Water and salt are formed
b)
The final pH is always 7
c)
Equal quantities of acid and base are needed
d)
The final pH is always 0
24.
Why are acids considered electrolytes?
a)
They dissociate in water to form anions and hydrogen cations
b)
They dissociate in water to form cations and hydroxide anions
c)
They are covalent compounds
d)
They cannot conduct an electric current in water
25.
Which is NOT a property of bases?
a)
Feels slippery when in contact with skin
b)
Tastes bitter
c)
Turns litmus paper blue
d)
Reacts with metals to form hydrogen gas
100 %
