Chapter 15 SMost of the elements in the periodic table can be described as: (metals, nonmetals, metalloids)cience

According to the periodic table in Figure 15-1, which group are the chemical elements that belong to the noble gases?

18

Chlorine, element number 17, is located in the third row and the next-to-the-last group of the periodic table. How many energy levels would be completely filled by a neutral atom of chlorine? How many electrons would be leftover?

2 energy level filled, 7 electrons left over

Using the periodic table in Figure 15-1, transition elements belong to groups:

3-12

How many energy levels are filled in a krypton atom?

4

An atom of nitrogen has how many electrons?

7

The diagram below represents information that can be found on the periodic table for the element helium. The atomic mass of a helium atom is indicated by the arrow at:

A

Steel can be described as:

An alloid mixture, conductor

Most of the elements in the periodic table can be described as: (metals, nonmetals, metalloids)

Metals

According to the periodic table in Figure 15-1, the group known as the halogens include the elements:

Fluorine, chlorine, bromine, iodine, astatine.

What are examples of a chemical property of a substance?

Forms molecules with hydrogen

A characteristic of elements that demonstrate the strongest periodicity is

Boiling point

Examples of metalloids, elements with properties between metals and nonmetals, are:

Boron, silicon, germanium, arsenic, antimony, tellurium, polonium, astatine.

The diagram below represents information that can be found on the periodic table for the element argon. The mass number for an argon isotope is represented at:

C

The element chlorine has two stable isotopes, Cl35 and Cl37. About 3 of every 4 chlorine atoms found on Earth are Cl35, and the remainder are Cl37. The average atomic mass of chlorine is closest to ____

Convert 3 out of 4 to a decimal and multiply by 35. Convert 1 out of 4 to a decimal and multiply by 37. Add those two answers together. 35.5

These elements make the best insulators:

Nonmetals such as sulfur.

An atomic mass unit is the approximate mass of a single:

Proton OR neutron.

According to the periodic table in Figure 15-1, transition metals include all of the elements EXCEPT:

Transition elements in groups 3-12 such as iron, copper, titanium, tungsten, manganese, etc.

Using the periodic table in Figure 15-1, all of the elements belong to the main group elements EXCEPT:

Transition metals such as iron, copper, titanium, tungsten, manganese, etc.

Of the following elements, the one most essential to life on Earth is:

carbon.

When the outermost energy level of an atom is filled, at room temperature, the resulting element:

does not interact strongly with other atoms and is often a gas at room temperature.

Materials that allow electricity to flow through easily are known as:

electrical conductors.

A period's number on the periodic table corresponds to the number of:

energy levels of the atoms in the period.

Elements used to make semiconductors for computers include germanium and: Germanium and silicon

germanium and silicon.

Most elements with high melting points have:

half-filled energy levels

The location of metals on the periodic table is on the:

left.

The element that is shiny in appearance, quite dense and liquid at room temperature is:

mercury.

The most abundant element in Earth's crust is:

oxygen.

An element essential to the manufacture of DNA and glow-in-the-dark plastic is;

phosphorus.

Most non-metals on the periodic table are located on the:

right.

Atomic mass is approximately the same as:

the mass number, the protons AND neutrons

The second row of the periodic table has 8 elements because:

the second energy level can hold 8 electrons.

The noble gases, such as helium and xenon, are non-reactive because

they have completely filled outer electron shells.

In which directions on the periodic table do the atomic masses of elements increase?

.Left to right and top to bottom

Alkali metals, highly reactive with oxygen, are found on the periodic table in Figure 15-1 in group: Group 1

1

The atomic mass of boron is 10.811. What is the mass number of the most abundant isotope of boron?

11