Question 1

The element antimony has an atomic weight of 121.757 amu and only two naturally-occurring isotopes.One isotope has an abundance of 57.3% and an isotopic mass of 120.904 amu.Based on these data,what is the mass of the other isotope?

Accepted Answer

The answer of The element antimony has an atomic weight...

Question 2

An element has two naturally occurring isotopes.One has an abundance of 37.4% and an isotopic mass of 184.953 amu,and the other has an abundance of 62.6% and a mass of 186.956 amu.What is the atomic weight of the element?

Accepted Answer

The answer of An element has two naturally occurring isotopes.One...

Question 3

The number of atoms of carbon in 12 g of carbon is closest to .

Accepted Answer

The answer of The number of atoms of carbon in...

Question 4

The smallest sample of carbon atoms that can be observed with the naked eye has a mass of approximately 2 × 10^-8 g.Given that 1 g = 6.02 × 10²³ amu,and that carbon has an atomic weight of 12.01 amu,determine the number of carbon atoms present in the sample.

Accepted Answer

First, convert the mass of the sample from grams to amu: 2 × 10^-8 g * (6.02 × 10^23 amu/g) = 1.204 × 10^16 amu. Then, divide by the atomic weight of carbon (12.01 amu) to find the number of atoms: 1.204 × 10^16 amu / 12.01 amu/atom ≈ 1 × 10^15 atoms.

Question 5

What is the chemical symbol for an atom that has 29 protons and 36 neutrons?

Accepted Answer

The chemical symbol for Copper is Cu, and an atom with 29 protons would be Copper. The other options do not have 29 protons.

Question 6

One mole of which element has the smallest mass?

Accepted Answer

Nickel (Ni) has the smallest atomic mass among the given elements.

Question 7

How many protons (p)and neutrons (n)are in an atom of 
?

Accepted Answer

The answer of How many protons (p)and neutrons (n)are in...

Question 8

What is the mass of one atom of the element hydrogen?

Accepted Answer

The mass of one atom of hydrogen is approximately 1.7 × 10-24 g, which is the mass of one atomic mass unit (amu). Choice A (2.0 g) and choice B (1.0 g) are far too large for the mass of one atom of hydrogen. Choice C (3.4 × 10-24 g) is close, but still not precise enough compared to the accepted value.

Question 9

How many protons (p)and neutrons (n)are in an atom of calcium-46?

Accepted Answer

The number beside the element name (in this case, 46) refers to the mass number, which is the total number of protons and neutrons. Since the atomic number of calcium is 20 (meaning it has 20 protons), we can subtract 20 from 46 to get the number of neutrons: 46 - 20 = 26. Therefore, the correct answer is A) 20 p, 26 n.

Question 10

How many protons (p),neutrons (n),and electrons (e)are in one atom of 
?

Accepted Answer

The atomic number of the element (11) tells us there are 11 protons in the nucleus. The given symbol (TB4939_11) indicates the atomic mass is 23, which means there are 23 - 11 = 12 neutrons. In a neutral atom, the number of electrons is equal to the number of protons, so there are also 11 electrons. Choice B matches these numbers.

Question 11

The atoms of a particular element all have the same number of protons as neutrons.Which of the following must be true?

Accepted Answer

The mass number is the sum of protons and neutrons in an atom's nucleus. If an element's atoms have the same number of protons and neutrons, then the mass number (protons + neutrons) would indeed be twice the atomic number (number of protons). Choices A and B are not necessarily true because the atomic weight of an element can be a decimal due to the presence of isotopes, and the atomic weight is an average that may not match the mass number of any specific atom.

Question 12

Which of the following two atoms are isotopes?

Accepted Answer

Isotopes are atoms of the same element with different numbers of neutrons. In option B, the two atoms have the same number of protons (S1) but a different number of neutrons (U1 and S1). Therefore, they are isotopes of sulfur. The other options do not have different numbers of neutrons and are not isotopes.

Question 13

How many electrons are in a neutral atom of iodine-131?

Accepted Answer

A neutral atom has the same number of electrons as protons. Iodine (I) has an atomic number of 53, indicating it has 53 protons and, therefore, 53 electrons in its neutral state.

Question 14

24.0 g of which element contains the greatest number of atoms?

Accepted Answer

Boron (B) has the lowest atomic mass among the given elements, so 24.0 g of boron contains the greatest number of atoms.

Question 15

The isotope represented by ^{is named}

Accepted Answer

The answer of The isotope represented by ^{is named} ...

Question 16

What is the standard isotope that is used to define the number of atoms in a mole?

Accepted Answer

The standard isotope used to define the number of atoms in a mole is carbon-12 (¹²C).

Question 17

Boron-9 can be represented as

Accepted Answer

Boron-9 has 5 electrons and 4 protons, so its symbol would be 5B. The first number in the ID numbers represents the atomic number, which should be 5. Option B is the only one where the first digit in the ID number is 5, so it is the correct option.

Question 18

Which are isotopes? An atom that has an atomic number of 34 and a mass number of 76 is an isotope of an atom that has

Accepted Answer

Isotopes are atoms of the same element with different numbers of neutrons. In this case, the atom with an atomic number of 34 and a mass number of 76 is an isotope of an atom with the same atomic number (34) but a different mass number (80). Therefore, option B is the correct choice. Option A has the same mass number but a different atomic number, which makes it a different element. Options C and D provide information about the number of neutrons and protons, but they do not match the given atom's characteristics, so they are not correct choices.

Question 19

Identify the chemical symbol of element Q in

Accepted Answer

The chemical symbol for selenium is Se, which matches element Q in the given code. The other options (Br, Hg, Pd) do not have the same chemical symbol as element Q.

Question 20

Which of the following represent isotopes?
[A: ]
[  B: ]
[  C: ]
[  D: ]

Accepted Answer

Isotopes have the same atomic number but different mass numbers. In the given options, only A and B have the same atomic number (11) and different mass numbers (7 and 9), hence they are isotopes. C and D have different atomic numbers, hence they cannot be isotopes.

Quiz 2: Atoms, molecules, and Ions

The element antimony has an atomic weight of 121.757 amu and only two naturally-occurring isotopes.One isotope has an abundance of 57.3% and an isotopic mass of 120.904 amu.Based on these data,what is the mass of the other isotope?

An element has two naturally occurring isotopes.One has an abundance of 37.4% and an isotopic mass of 184.953 amu,and the other has an abundance of 62.6% and a mass of 186.956 amu.What is the atomic weight of the element?

The number of atoms of carbon in 12 g of carbon is closest to .

The smallest sample of carbon atoms that can be observed with the naked eye has a mass of approximately 2 × 10^-8 g.Given that 1 g = 6.02 × 10²³ amu,and that carbon has an atomic weight of 12.01 amu,determine the number of carbon atoms present in the sample.

What is the chemical symbol for an atom that has 29 protons and 36 neutrons?

One mole of which element has the smallest mass?

How many protons (p) and neutrons (n) are in an atom of ?

What is the mass of one atom of the element hydrogen?

How many protons (p) and neutrons (n) are in an atom of calcium-46?

How many protons (p) ,neutrons (n) ,and electrons (e) are in one atom of ?

The atoms of a particular element all have the same number of protons as neutrons.Which of the following must be true?

Which of the following two atoms are isotopes?

How many electrons are in a neutral atom of iodine-131?

24.0 g of which element contains the greatest number of atoms?

The isotope represented by ^{is named}

What is the standard isotope that is used to define the number of atoms in a mole?

Boron-9 can be represented as

Which are isotopes? An atom that has an atomic number of 34 and a mass number of 76 is an isotope of an atom that has

Identify the chemical symbol of element Q in

Which of the following represent isotopes? [A: ] [ B: ] [ C: ] [ D: ]

Quiz 2: Atoms, molecules, and Ions

The element antimony has an atomic weight of 121.757 amu and only two naturally-occurring isotopes.One isotope has an abundance of 57.3% and an isotopic mass of 120.904 amu.Based on these data,what is the mass of the other isotope?

An element has two naturally occurring isotopes.One has an abundance of 37.4% and an isotopic mass of 184.953 amu,and the other has an abundance of 62.6% and a mass of 186.956 amu.What is the atomic weight of the element?

The number of atoms of carbon in 12 g of carbon is closest to .

The smallest sample of carbon atoms that can be observed with the naked eye has a mass of approximately 2 × 10-8 g.Given that 1 g = 6.02 × 1023 amu,and that carbon has an atomic weight of 12.01 amu,determine the number of carbon atoms present in the sample.

What is the chemical symbol for an atom that has 29 protons and 36 neutrons?

One mole of which element has the smallest mass?

How many protons (p) and neutrons (n) are in an atom of ?

What is the mass of one atom of the element hydrogen?

How many protons (p) and neutrons (n) are in an atom of calcium-46?

How many protons (p) ,neutrons (n) ,and electrons (e) are in one atom of ?

The atoms of a particular element all have the same number of protons as neutrons.Which of the following must be true?

Which of the following two atoms are isotopes?

How many electrons are in a neutral atom of iodine-131?

24.0 g of which element contains the greatest number of atoms?

The isotope represented by is named

What is the standard isotope that is used to define the number of atoms in a mole?

Boron-9 can be represented as

Which are isotopes? An atom that has an atomic number of 34 and a mass number of 76 is an isotope of an atom that has

Identify the chemical symbol of element Q in

Which of the following represent isotopes? [A: ] [ B: ] [ C: ] [ D: ]

The smallest sample of carbon atoms that can be observed with the naked eye has a mass of approximately 2 × 10^-8 g.Given that 1 g = 6.02 × 10²³ amu,and that carbon has an atomic weight of 12.01 amu,determine the number of carbon atoms present in the sample.

The isotope represented by ^{is named}