Science Chapter 5
An electron that is in the highest occupied energy level of an atom is ...?
a valence electron
The reactivity of alkali metals does what from the top of Group 1a to the bottom
Sodium is stored under oil because why?
It reacts highly with water.
The differences in reactivity among alkaline earth metals are shown by the way they react with what?
What is the main ingredient in limestone?
What helps build strong bones and teeth?
What are the four metals in Group 3A?
What is the most abundant metal in the Earth's crust AND is a good conductor of electric current
What are the two metaloids in Group 4A?
Except for water, most of the compounds in your body contain what element?
What are the non metals in Group 5A
Nitrogen and Phosporus
Name two elements in the nitrogen family that are contained in fertilizer?
nitrogen and phosphorus
List the three non metals in group 6A
Name the most abundant element in the earth's crust?
List the four non metals in Group 7A
Halogens have ________ properties but different ___________ properties.
similar chemical properties
different physical properties
Name three characteristics of noble gases
How can an element that does not react easily with other elements be useful?
preventing other elements from reacting
Is it true or false that the first elements to be identified were gases?
As the number of known elements grew, so did the need to organize them into groups based on their what?
What categories of elements did French chemist Antoine Lavoisier use to classify
Is it true or false that Mendeleev needed to organize information about 63 elements?
Mendeleev's strategy for classifying elements was modeled on what?
a card game
What type of information did Mendeleev know about each element?
How did Mendeleev arrange the elements into rows?
By mass, so that elements with similar properties were in the same column.
Is it true that a periodic table is an arrangement of elements in columns based on a set of properties that repeat from row to row?
Menedleev published the table he made in 1872. Why did he leave some locations in his periodic table blank?
For undiscovered elements
Which of the following elements have similar properties?
In the modern period table, elements are arranged by increasing number of what?
Explain why the number of elements per period varies.
the number of orbitals various between energy levels
Properties of elements repeat in a predictable way when atomic numbers are used to arrange elements into groups. What is this pattern of repeating properties called?
What is atomic mass
The value that depends on distributions of an element's isotopes in nature and their masses.
How many protons and neutrons does Carbon-12 have?
What is used as the standard for comparing the masses of atoms?
How is an atomic mass unit defined
One twelfth of the mass of a carbon-12 atom
Is it true or false that most elements exist as a misture of two or more isotopes?
Is the mass of an atom of chlorine-37 greater or less than the mass of an atom of chlorine-35?
Is it true or false that all values are equally important in a weighted average?
Name the three categories into which elements are classified based on their general properties
Do all metals react with oxygen in the same way?
What is an important property of transition elements?
their ability to form compounds with distinctive colors
Are nonmetals good conductors of heat and electric current
Are many nonmetals gases at room temperature
Are all non metals extremely reactive ?
Nonmetals that are solids tend to be what?
Across a period from left to right, the elements become ____ metalic and more ________.
they become less metalic and more nonmetallic.
Which of the below period 3 elements below are highly reactive?
Science Chapter 5