thanks for helping me Everyone
. why do we classify the elements?
Answers
Answer:
MARK ME BRALIEST
Elements can be classified as metals, metalloids, and nonmetals, or as a main-group elements, transition metals, and inner transition metals. Groups are numbered 1–18 from left to right. The elements in group 1 are known as the alkali metals; those in group 2 are the alkaline earth metals; those in 15 are the pnictogens; those in 16 are the chalcogens; those in 17 are the halogens; and those in 18 are the noble gases.
EXERCISES
Metal or Nonmetal?
Using the periodic table, classify each of the following elements as a metal or a nonmetal, and then further classify each as a main-group (representative) element, transition metal, or inner transition metal:
uranium
bromine
strontium
neon
gold
americium
rhodium
sulfur
carbon
potassium
Using the periodic table, classify each of the following elements as a metal or a nonmetal, and then further classify each as a main-group (representative) element, transition metal, or inner transition metal:
cobalt
europium
iodine
indium
lithium
oxygen
cadmium
terbium
rhenium
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Identifying Elements
Using the periodic table, identify the lightest member of each of the following groups:
noble gases
alkaline earth metals
alkali metals
chalcogens
Using the periodic table, identify the heaviest member of each of the following groups:
alkali metals
chalcogens
noble gases
alkaline earth metals
Use the periodic table to give the name and symbol for each of the following elements:
the noble gas in the same period as germanium
the alkaline earth metal in the same period as selenium
the halogen in the same period as lithium
the chalcogen in the same period as cadmium
Use the periodic table to give the name and symbol for each of the following elements:
the halogen in the same period as the alkali metal with 11 protons
the alkaline earth metal in the same period with the neutral noble gas with 18 electrons
the noble gas in the same row as an isotope with 30 neutrons and 25 protons
the noble gas in the same period as gold
Write a symbol for each of the following neutral isotopes. Include the atomic number and mass number for each.
the alkali metal with 11 protons and a mass number of 23
the noble gas element with and 75 neutrons in its nucleus and 54 electrons in the neutral atom
the isotope with 33 protons and 40 neutrons in its nucleus
the alkaline earth metal with 88 electrons and 138 neutrons
Write a symbol for each of the following neutral isotopes. Include the atomic number and mass number for each.
the chalcogen with a mass number of 125
the halogen whose longest-lived isotope is radioactive
the noble gas, used in lighting, with 10 electrons and 10 neutrons
the lightest alkali metal with three neutrons
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Explanation:
Due to discovery of different elements, it was difficult to organize the information and properties of the elements, so there was a strong need to find some pattern in the properties of different elements so that they can be grouped together. That's why we classify elements.