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8th Science section II Objective four test - Hager
1.
Which of the following will tell you the most about an unknown element?
A. it’s mass
B. It’s conductivity
C. it’s family
D. it’s period
2.
Three objects were dropped into a tank of water. One sank halfway down, one sank to the
bottom, one floated. What was being tested?
A. solubility
B. polarity
C. buoyancy
D. cohesion
A student combined the reactants of 215.8 grams of silver and 32.1 grams of sulfur which
yielded the product of silver sulfide. What is the most likely estimate of the mass of the product?
A. 184 g
B.247 g
C. 248 g
D. 300 g
3.
4.
How is H2O different than H2 and O2 from which it is composed (at room temperature)?
A. H2O and H2 are liquids, O2 is a gas
C. H2O is a solid, H2 and O2 are gases
5.
Which is a result of water being the universal solvent?
A. It changes form
6.
B. H2O and H2 are gas, O2 is a liquid
D. H2O is a liquid, H2 and O2 are gases
B. all life needs it
C. it is rarely found pure in nature
To determine if an object is made of pure silver which of the following is the best procedure?
A. test it’s solubility B. test it’s reactivity C. compare density to pure silver D. compare it’s mass
7.
Which of the following are typical indicators of a chemical reaction?
A. Percipitants
8.
B. bubble formation
C. color change
D. all three and more
Oil floats in water while mercury will sink in water. What is the best explanation for this
observation?
A. Water is lighter than mercury, heavier than oil
B. oil doesn’t react with water, mercury does
C. Water is less dense than mercury, more dense than oil D. cohesion forces oil to rise and mercury to sink
9.
Ionic bonds stick together with charges in the atoms and covalent bonds share electrons. But
why is water so sticky if it is a covalent bond?
A. It’s polar - sharing unequally
C. It beads on most surfaces
B. it is the universal solvent
D. it is liquid at room temperature
10.
Glucose reacts with Oxygen to yield Carbon dioxide and water. Which of the following requires
a balanced equation?
A. conservation of energy
B. conservation of mass
C. equilibrium
D. saturation
11.
In a chemical reaction we have
x2 + y2  xy + energy.
What must we add to the product to show conservation of mass?
A.
An ‘x2y2’ compound
B. another ‘xy’ compound
C. An ‘x’
D. An
‘y’
12.
In the reaction from #2 above: what kind of reaction is this?
A. endothermic
13.
B. exothermic
C. reduction
D. oxidation
The reaction in #11 demonstrates that chemical reactions do which of the following?
A. atoms are made of subatomic particles
B. compounds break down and recombine to form new compounds
C. Matter is created when a chemical reaction takes place
D. molecules combine to form elements
14.
Halogens, which form salts with groups one and two, are also used in which of the following
ways?
A. to kill bacteria
15.
B. to eliminate odor
C. to filter sediments
D. to store foods
If two reactants of a certain mass are chemically combined in an open beaker, and some
mass appears to have been lost, what is the best explanation?
A. a gas was produced
B. a solid was produced
C. salinity was high
D. the temperature was low.
16.
Why can insects walk across the surface of a pond?
A. adhesion
17.
B. surface tension
C. non-polarity of water
D. capillary action
Water will stick to most surfaces. Which best explains this observation?
A. adhesion
B. surface tension
C. capillary action
D. water is non-polar
18.
A beaker of 100 ml of water on a heater will boil at 100 degrees Celsius. At how many degrees
will 90 ml of water boil?
A 100 C
B. 90 C
C. 10 C
D. 110 C
19.
Which substance listed would heat up the fastest if exposed to the same temperature for the
same amount of time?
Specific Heat of each is listed here: (Lead 128 C)
(Iron 448 C) (Glass 837 C) (Ice 2090 C)
A. Lead
20.
B. Ice
D. Glass
How can a scientist find an element that has similar characteristic as another element?
A. Look at the period
C. comparing it’s malleability
21.
C. Iron
B. finding the periodic family
D. comparing atomic mass
Which of the following examples is a physical change?
A. burning paper
B. rusting nail
C. rotting wood
D. melting plastic
22.
Which element has 8 protons in all of its atoms?
Atm #
19
1
8
A. Potassium
B. Hydrogen
C. Oxygen
6
D. Carbon
23. In the figure below; What do the black upward arrows represent?
A. Bouyant Force B. Displacment
C. Gravitational impact
D. Surface tension
Figure 1
24. In the image above: what do the white arrows pointing down represent?
A. Bouyant Force B. Displacment
C. Gravitational impact
D. Surface tension
25. In figure 2 below: what property of water allows it to pile up or stand up on a car or penny?
A. surface tension
B. adhesion
C. ionic bonding
D. covalent bonding
Figure 2
26. In figure 3 above: capillary action allows water to climb up these two tubes in the tank?
Which property of water causes or creates capillary action?
A. adhesion
B. air pressure
C. cohesion
D. surface tension
27. In figure 4 below: What are the products of this chemical reaction?
A. water
B. carbon dioxide C. C6H12O6 and O6
D. oxygen
Figure 4
28. In the figure 4 above: What does the plus mean on the reactants side of the equation?
A. These compounds are being mixed B. These compounds are changing bonds with one another
C. These compounds are not changing
D. These compounds are similar