Question 1

Elements in group 17 (VIIA) are called __________

Accepted Answer

Elements in group 17 are known as halogens.

Question 2

Cobalt is best described as a __________

Accepted Answer

Cobalt is a transition metal, located in the central block of the periodic table. It has properties similar to other transition metals, such as iron and nickel, and is commonly used in alloys and magnetic materials.

Question 3

Sodium is best described as a __________

Accepted Answer

Sodium is a highly reactive alkali metal with metallic properties such as high electrical conductivity, luster, and malleability.

Question 4

For each of the elements below, there are only two naturally occurring isotopes. Using information in your periodic table, identify the pair in which the heavier isotope is the more abundant one.

Accepted Answer

The answer of For each of the elements below, there...

Question 5

He is the symbol for __________

Accepted Answer

The symbol "He" represents the element helium.

Question 6

Silicon is best described as a __________

Accepted Answer

Silicon is a metalloid, meaning it has properties of both metals and nonmetals. It has some metallic properties such as being a good conductor of electricity, but also has some non-metallic properties such as being brittle and having a lower melting point than most metals.

Question 7

Elements in group 18 (VIIIA) are called __________

Accepted Answer

Elements in group 18 are called noble gases because they have a full outermost shell of electrons, making them chemically stable and resistant to forming compounds with other elements.

Question 8

A hypothetical element has two stable isotopes: one isotope has a mass of 106.9051 amu with an abundance of 48.183%, the other isotope has a mass of 108.9048 amu with an abundance of 51.825%. What is the average atomic mass of this element?

Accepted Answer

The answer of A hypothetical element has two stable isotopes:...

Question 9

The average atomic mass of zinc is 65.39 amu. Given the data in the following table, what is the natural abundance of ⁶⁶Zn? Isotope Mass (amu) Natural Abundance (%)⁶⁴Zn 63)9291 48)89⁶⁶Zn 65)9260 ?⁶⁷Zn 66)9271 4)11⁶⁸Zn 67)9249 18)56⁷⁰Zn 69)9253 0)62

Accepted Answer

The natural abundance of an isotope is equal to its percentage abundance. From the table, the natural abundance of ⁶⁶Zn is 27.81%.

Question 10

Zinc has five naturally occurring isotopes with an average mass of 65.39 amu. Three isotopes, in roughly equal amounts, account for 95% of zinc. Which isotope is most abundant?

Accepted Answer

The answer of Zinc has five naturally occurring isotopes with...

Question 11

Which of the following is an alkali metal?

Accepted Answer

Alkali metals are the elements in group 1 of the periodic table: hydrogen (H), lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr). Out of the given options, only K (potassium) belongs to group 1 and is an alkali metal.

Question 12

For each of the elements below, there are only two naturally occurring isotopes. Using information in your periodic table, identify the pair in which the lighter isotope is the more abundant one.

Accepted Answer

The lighter isotope of bromine, ⁷⁹Br, has a higher abundance (50.69%) compared to the heavier isotope, ⁸¹Br (49.31%). Answer: C The lighter isotope of boron, ¹⁰B, has a higher abundance (80.1%) compared to the heavier isotope, ¹¹B (19.9%). Both A, D, and E have only one naturally occurring isotope.

Question 13

What is the symbol for sulfur?

Accepted Answer

The symbol for sulfur is represented by the letter "S" in the periodic table.

Question 14

The average atomic mass of lithium is 6.941 amu. Lithium has two naturally occurring isotopes, ⁶Li (7.52%) and ⁷Li (92.48%). The mass of ⁶Li is 6.0151 amu. What is the mass of ⁷Li?

Accepted Answer

The answer of The average atomic mass of lithium is...

Question 15

An unknown element is found to contain isotopes with the following masses and natural abundances: 38.9637 amu (93.08%), 39.9640 amu (0.012%), and 40.9618 amu (6.91%). Using these data, identify the element.

Accepted Answer

The given data shows that the element has three isotopes with masses of 38.9637 amu, 39.9640 amu, and 40.9618 amu, and their natural abundances are 93.08%, 0.012%, and 6.91%, respectively. The atomic mass of the element can be calculated by adding the products of each isotope's mass and abundance:

(38.9637 amu)(0.9308) + (39.9640 amu)(0.00012) + (40.9618 amu)(0.0691) = 39.0983 amu

This value is closest to the atomic mass of potassium (39.0983 amu). Therefore, the unknown element is most likely potassium (K).

Question 16

Elements 21 through 30 are known as __________

Accepted Answer

Elements 21 through 30 are transition metals.

Question 17

Enriched weapons-grade uranium consists of 80% uranium-235 (235.044 amu) and 20% uranium-238 (238.051 amu). What is the average atomic mass of weapons grade uranium assuming the percentages are exact?

Accepted Answer

To find the average atomic mass of weapons-grade uranium, we must use the weighted average formula:

Average atomic mass = (% abundance of U-235 x mass of U-235) + (% abundance of U-238 x mass of U-238)

Plugging in the given values, we get:

Average atomic mass = (0.80 x 235.044 amu) + (0.20 x 238.051 amu) 
= 188.0352 amu + 47.6102 amu 
= 235.6454 amu

Rounding off to the nearest hundredth gives us an answer of 235.65 amu, which is closest to choice D (235.645 amu).

Question 18

Calcium is an example of __________

Accepted Answer

Calcium belongs to group 2 of the periodic table, also known as the alkaline earth metals.

Question 19

Oxygen is best described as a __________

Accepted Answer

Oxygen is a nonmetal. It is located in the nonmetal group of the periodic table and has properties such as poor conductivity, high electronegativity, and a tendency to gain electrons in chemical reactions.

Question 20

What is the symbol for magnesium?

Accepted Answer

The chemical symbol for magnesium is Mg, which is derived from its name in Latin "magnesia."

Quiz 2: Atoms, Ions, and Compounds

Elements in group 17 (VIIA) are called __________

Cobalt is best described as a __________

Sodium is best described as a __________

For each of the elements below, there are only two naturally occurring isotopes. Using information in your periodic table, identify the pair in which the heavier isotope is the more abundant one.

He is the symbol for __________

Silicon is best described as a __________

Elements in group 18 (VIIIA) are called __________

A hypothetical element has two stable isotopes: one isotope has a mass of 106.9051 amu with an abundance of 48.183%, the other isotope has a mass of 108.9048 amu with an abundance of 51.825%. What is the average atomic mass of this element?

The average atomic mass of zinc is 65.39 amu. Given the data in the following table, what is the natural abundance of ⁶⁶Zn? Isotope Mass (amu) Natural Abundance (%) ⁶⁴Zn 63) 9291 48) 89⁶⁶Zn 65) 9260 ?⁶⁷Zn 66) 9271 4) 11⁶⁸Zn 67) 9249 18) 56⁷⁰Zn 69) 9253 0) 62

Zinc has five naturally occurring isotopes with an average mass of 65.39 amu. Three isotopes, in roughly equal amounts, account for 95% of zinc. Which isotope is most abundant?

Which of the following is an alkali metal?

For each of the elements below, there are only two naturally occurring isotopes. Using information in your periodic table, identify the pair in which the lighter isotope is the more abundant one.

What is the symbol for sulfur?

The average atomic mass of lithium is 6.941 amu. Lithium has two naturally occurring isotopes, ⁶Li (7.52%) and ⁷Li (92.48%) . The mass of ⁶Li is 6.0151 amu. What is the mass of ⁷Li?

An unknown element is found to contain isotopes with the following masses and natural abundances: 38.9637 amu (93.08%) , 39.9640 amu (0.012%) , and 40.9618 amu (6.91%) . Using these data, identify the element.

Elements 21 through 30 are known as __________

Enriched weapons-grade uranium consists of 80% uranium-235 (235.044 amu) and 20% uranium-238 (238.051 amu) . What is the average atomic mass of weapons grade uranium assuming the percentages are exact?

Calcium is an example of __________

Oxygen is best described as a __________

What is the symbol for magnesium?

Quiz 2: Atoms, Ions, and Compounds

Elements in group 17 (VIIA) are called __________

Cobalt is best described as a __________

Sodium is best described as a __________

For each of the elements below, there are only two naturally occurring isotopes. Using information in your periodic table, identify the pair in which the heavier isotope is the more abundant one.

He is the symbol for __________

Silicon is best described as a __________

Elements in group 18 (VIIIA) are called __________

A hypothetical element has two stable isotopes: one isotope has a mass of 106.9051 amu with an abundance of 48.183%, the other isotope has a mass of 108.9048 amu with an abundance of 51.825%. What is the average atomic mass of this element?

The average atomic mass of zinc is 65.39 amu. Given the data in the following table, what is the natural abundance of 66Zn? Isotope Mass (amu) Natural Abundance (%) 64Zn 63) 9291 48) 8966Zn 65) 9260 ?67Zn 66) 9271 4) 1168Zn 67) 9249 18) 5670Zn 69) 9253 0) 62

Zinc has five naturally occurring isotopes with an average mass of 65.39 amu. Three isotopes, in roughly equal amounts, account for 95% of zinc. Which isotope is most abundant?

Which of the following is an alkali metal?

For each of the elements below, there are only two naturally occurring isotopes. Using information in your periodic table, identify the pair in which the lighter isotope is the more abundant one.

What is the symbol for sulfur?

The average atomic mass of lithium is 6.941 amu. Lithium has two naturally occurring isotopes, 6Li (7.52%) and 7Li (92.48%) . The mass of 6Li is 6.0151 amu. What is the mass of 7Li?

An unknown element is found to contain isotopes with the following masses and natural abundances: 38.9637 amu (93.08%) , 39.9640 amu (0.012%) , and 40.9618 amu (6.91%) . Using these data, identify the element.

Elements 21 through 30 are known as __________

Enriched weapons-grade uranium consists of 80% uranium-235 (235.044 amu) and 20% uranium-238 (238.051 amu) . What is the average atomic mass of weapons grade uranium assuming the percentages are exact?

Calcium is an example of __________

Oxygen is best described as a __________

What is the symbol for magnesium?

The average atomic mass of zinc is 65.39 amu. Given the data in the following table, what is the natural abundance of ⁶⁶Zn? Isotope Mass (amu) Natural Abundance (%) ⁶⁴Zn 63) 9291 48) 89⁶⁶Zn 65) 9260 ?⁶⁷Zn 66) 9271 4) 11⁶⁸Zn 67) 9249 18) 56⁷⁰Zn 69) 9253 0) 62

The average atomic mass of lithium is 6.941 amu. Lithium has two naturally occurring isotopes, ⁶Li (7.52%) and ⁷Li (92.48%) . The mass of ⁶Li is 6.0151 amu. What is the mass of ⁷Li?