`In an atom of Ar-41, how many neutrons would there be?
A.
18
B.
41
C.
59
D.
23
E.
none of the above
If iodine were to form an ion, what would its charge be?
A.
2-
B.
1+
C.
1-
D.
2+
E.
none of the above
How would you correctly write the atomic symbol of nitrogen?
A.
Ni
B.
Ng
C.
Nt
D.
N
E.
none of the above
All of the following are characteristics of metals except:
A.
malleable
B.
often lustrous
C.
ductile
D.
tend to gain electrons in chemical reactions E.
good conductors of heat
Rutherford's experiment with alpha particle scattering by gold foil established that:
A.
protons are not evenly distributed throughout an atom.
B.
protons are 1840 times heavier than electrons.
C.
electrons have a positive charge.
D.
atoms are made of protons, neutrons, and electrons.
E.
electrons have a negative charge.
Who discovered the law of conservation of mass?
A.
Albert Einstein
B.
Antoine Lavoisier
C.
none of these.
D.
John Dalton and Antoine Lavoisier
E.
John Dalton
`Which of the following statements is true as stated by the chemist Joseph proust?
A.
All atoms of a given element have a constant composition and are different than atoms of any other element.
B.
All samples of a given compound have the same proportions of their constituent elements.
C.
The nucleus is a dense region of positive charge that always contains protons and neutrons.
D.
Matter cannot be either created or destroyed in a chemical reaction.
The symbol that is usually used to represent atomic number is:
A.
N
B.
A
C.
Z
D.
X
`In an atom of Be-8, how many neutrons would there be?
A.
8
B.
9
C.
4
D.
12
E.
none of the above
The symbol for bromine is:
A.
none of these
B.
Be
C.
Br
D.
B
I recently had my house fumigated with methyl bromide (CH3Br).
I paid for 2.00 kg of CH3Br.
How many moles does this represent?
A.
94.9
B.
2.11 × 10-2
C.
21.1
D.
189.9
Silver salts have antimicrobial properties--they can kill bacteria by interfering with certain proteins.
Silver nitrate used to be given in drop form to newborns to prevent them from contracting gonorrhea from infected mothers.
How many oxygen atoms would be in 2.0 moles of silver nitrate?
A.
6.0
B.
6.022 x 1023
C.
3.61 x 1024
D.
1.20 x 1024
I have a skillet that is not cast iron, but rather pure iron.
It has a mass of 8.000 pounds.
How many moles of iron are in my skillet? Remember there are 453.5 grams in a pound.
A.
64.97
B.
0.1433
C.
8.121
D.
2.026 × 105
1.00 mole of O2 contains the same number of molecules as:
A.
0.667 mole of O3.
B.
All of these
C.
1.00 mole of CH3CO2H.
D.
2.00 mole of CH3CH2OH.
Elemental bromine gas can be used to disinfect hot tubs and pools.
What would be the mass of one 4.0/ 4.0 Points mole of this gas?
A.
79.9
B.
6.022 × 1023
C.
159.81
D.
35
E.
none of the above
`If I tell you the mass ratio of H to P in a compound is 0.0968, which of the following could it be?
A.
PH2.
B.
PH6.
C.
PH.
D.
PH3.
E.
none of the above
What is the molar mass of a substance if 0.274 moles of it weighs 62.5 g? A.
4.38 × 10-3 g/mol
B.
6.02 x 1023 g/mol
C.
2.17 × 102 g/mol
D.
2.28 × 102 g/mol
E.
1.71 × 101 g/mol
That nasty rotten egg smell is not actually gaseous sulfur, but rather hydrogen sulfide, or more
properly named hydrosulfuric acid.
It is heavier than air, too, so it tends to stick around for a while to share its delectible aroma.
One mole of this compound would contain:
A.
2 moles of hydrogen.
B.
2 moles of sulfur.
C.
1 mole of hydrogen.
D.
4 moles of oxygen.
E.
4 moles of sulfur
I got in trouble a lot at school.
One time it was for throwing sticks of chalk at my chemistry teacher, 4.0/ 4.0 Points and my punishment was to write "I will not throw ___ moles of calcium carbonate at the teacher," meaning I had to solve a problem as part of the punishment.
I used a balance to figure out that a stick of chalk (calcium carbonate) had a mass of 5.0 g.
So what was the number that went in the blank?
A.
100.1
B.
0.096
C.
52.1
D.
10.5
E.
0.050
My friend has been isolating gold foils from gold plated electronic equipment.
He recently was able4.0/ 4.0 Points to take a 3.00 gram gold nugget to sell to a buyer.
How many moles of gold were in his nugget?
A.
0.0152
B.
197
C.
591
D.
107.9
E.
0.0278
As ice cools from 273 K to 263 K, the average kinetic energy of its molecules will:
A.
increase
B.
none of these
C.
remain the same
D.
decrease
How many calories are in 25 Calories?
A.
250
B.
2500
C.
25000
D.
25
Which of these is a common unit of energy?
A.
joule
B.
kJ
C.
kilowatt-hour D.
calorie
E.
all of the above
A certain reaction is exothermic.
Therefore, the reverse of this same reaction must be a(n)
A.
isothermal process.
B.
exothermic process.
C.
chemical change.
D.
endothermic process.
E.
none of the above
For a process at constant pressure, 49,600 calories of heat are released.
This quantity of heat is equivalent to:
A.
1.19 × 104 J
B.
1.24 × 104 J
C.
4.82 × 10-6 J
D.
2.08 × 105 J