Question 1

Why is CaO the symbol for calcium oxide instead of CAO?

Accepted Answer

A)  both can be the symbols for calcium oxide
B)  both are incorrect; the symbol is cao
C)  a capital letter means a new symbol
D)  both are incorrect as the symbol should be CaOxE) C) and D)
F) B) and D)

Question 2

Determine the number of electrons and protons in the element Tc.

Accepted Answer

A)  43 protons,43 electrons
B)  43 protons,56 electrons
C)  56 protons,43 electrons
D)  99 protons,43 electronsE) A) and D)
F) B) and C)

Question 3

How many hydrogen atoms are in 1.00 mole of NH3?

Accepted Answer

A)  3.00
B)  6.02* 1023
C)  12.0 *1023
D)  18.1 * 1023E) All of the above
F) A) and B)

Question 4

Isotopes of the same element always have the same number of neutrons.

Accepted Answer

A) True 
 B)False

Question 5

Which of the following carries a negative charge?

Accepted Answer

A)  a proton
B)  a neutron
C)  an electron
D)  both proton and neutronE) B) and C)
F) C) and D)

Question 6

Which element is approximately 65 percent of sulfuric acid by weight?

Accepted Answer

A)  hydrogen
B)  sulfur
C)  oxygen
D)  any of theseE) A) and C)
F) B) and D)

Question 7

How many neutrons are found in the nucleus of a boron-11 (11B) atom?

Accepted Answer

A)  11
B)  6
C)  5
D)  4E) None of the above
F) B) and C)

Question 8

The weight % of S in K2SO4 is _____ .

Accepted Answer

A)  14.2%
B)  18.4%
C)  54.4%
D)  22.4%E) All of the above
F) B) and D)

Question 9

How many carbon atoms are contained in 5.50 g of ethane,C2H6?

Accepted Answer

A)  2.75 *10-22
B)  3.29 * 1024
C)  1.10 * 1023
D)  2.21 * 1023E) A) and D)
F) B) and C)

Question 10

If you have 3.011 *1023 atoms of carbon,what would you expect its mass to be?

Accepted Answer

A)  12.01 g
B)  6.005 g
C)  3.003 g
D)  1.000 gE) B) and C)
F) All of the above

Question 11

The system of atomic mass units is based on

Accepted Answer

A)  assigning 12C as weighing exactly 12 u & comparing other elements to it.
B)  measuring the true mass of each subatomic particle.
C)  comparing the differences in protons and electrons.
D)  viewing how atoms are affected by electromagnetic fields.E) None of the above
F) A) and C)

Question 12

Oxalic acid is found in many plants,like spinach and black tea.What is the mass of the carbon found in one mole of oxalic acid,H2C2O4?

Accepted Answer

A)  12.01 g of C
B)  24.02 g of Cl
C)  45.01 g of C
D)  90.02 g of CE) B) and D)
F) A) and D)

Question 13

The symbol for bromine is _____ .

Accepted Answer

A)  B
B)  Br
C)  Be
D)  none of theseE) B) and D)
F) A) and D)

Question 14

How many neutrons are in an atom that has a mass number of 75 and contains 35 protons?

Accepted Answer

A)  40
B)  35
C)  75
D)  can't tellE) All of the above
F) A) and C)

Question 15

Determine the molecular weight of hydrogen peroxide,H2O2,in u (or amu) .

Accepted Answer

A)  17.01
B)  18.02
C)  34.02
D)  33.01E) A) and B)
F) All of the above

Question 16

Protons and neutrons have approximately the same mass.

Accepted Answer

A) True 
 B)False

Question 17

How many moles of hydrogen molecules (H2) would be required to produce two moles of hydrogen peroxide (H2O2) ?

Accepted Answer

A)  1
B)  2
C)  3
D)  4E) None of the above
F) A) and C)

Question 18

One mole of any substance will contain one Avogadro's number of atoms of that substance.

Accepted Answer

A) True 
 B)False

Question 19

Refer to a periodic table and tell how many helium atoms (He) would be needed to get close to the same mass as an average oxygen atom (O) .

Accepted Answer

A)  six
B)  four
C)  twelve
D)  one-fourthE) None of the above
F) All of the above

Question 20

Atoms are neutral.How can they have no charge?

Accepted Answer

A)  equal numbers of protons and neutrons
B)  equal numbers of protons and electrons
C)  equal numbers of neutrons and electrons
D)  any charge has been drained out of the atomE) B) and D)
F) All of the above

Exam 2: Atoms and Molecules

The weight % of S in K2SO4 is _____ .

Correct AnswerverifiedShow Answer

If you have 3.011 *1023 atoms of carbon,what would you expect its mass to be?

Correct AnswerverifiedShow Answer

Why is CaO the symbol for calcium oxide instead of CAO?

Correct AnswerverifiedShow Answer

How many neutrons are in an atom that has a mass number of 75 and contains 35 protons?

Correct AnswerverifiedShow Answer

Which element is approximately 65 percent of sulfuric acid by weight?

Correct AnswerverifiedShow Answer

How many hydrogen atoms are in 1.00 mole of NH3?

Correct AnswerverifiedShow Answer

The system of atomic mass units is based on

Correct AnswerverifiedShow Answer

How many moles of hydrogen molecules (H2) would be required to produce two moles of hydrogen peroxide (H2O2) ?

Correct AnswerverifiedShow Answer

Determine the molecular weight of hydrogen peroxide,H2O2,in u (or amu) .

Correct AnswerverifiedShow Answer

Protons and neutrons have approximately the same mass.

Correct AnswerverifiedShow Answer

Oxalic acid is found in many plants,like spinach and black tea.What is the mass of the carbon found in one mole of oxalic acid,H2C2O4?

Correct AnswerverifiedShow Answer

Refer to a periodic table and tell how many helium atoms (He) would be needed to get close to the same mass as an average oxygen atom (O) .

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Determine the number of electrons and protons in the element Tc.

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Atoms are neutral.How can they have no charge?

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How many neutrons are found in the nucleus of a boron-11 (11B) atom?

Correct AnswerverifiedShow Answer

How many carbon atoms are contained in 5.50 g of ethane,C2H6?

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One mole of any substance will contain one Avogadro's number of atoms of that substance.

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The symbol for bromine is _____ .

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Isotopes of the same element always have the same number of neutrons.

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Which of the following carries a negative charge?

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The weight % of S in K₂SO₄ is _____ .

Correct Answer
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If you have 3.011 *10²³ atoms of carbon,what would you expect its mass to be?

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How many hydrogen atoms are in 1.00 mole of NH₃?

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How many moles of hydrogen molecules (H₂) would be required to produce two moles of hydrogen peroxide (H₂O₂) ?

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Determine the molecular weight of hydrogen peroxide,H₂O₂,in u (or amu) .

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Oxalic acid is found in many plants,like spinach and black tea.What is the mass of the carbon found in one mole of oxalic acid,H₂C₂O₄?

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How many neutrons are found in the nucleus of a boron-11 (¹¹B) atom?

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How many carbon atoms are contained in 5.50 g of ethane,C₂H₆?

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