1.Vertical columns in the periodic table indicate what information?
A.periods
B.liquids
C.synthetic elements
D.groups and families

2.Which of these are families of elements?
A.metals and noble gases
B.shells and nonmetals
C.properties and rare earth elements
D.metalloids and atoms

3.Why is the atomic mass of many elements not a whole number?
A.Elements are unstable.
B.An element may have isotopes with different numbers of neutrons.
C.The atomic mass includes all the electrons.
D.lsotopes are always expressed in decimals.

The correct answers to the following questions are :
(1) Vertical columns in the periodic table indicate D.groups and families
(2) families of elements includes A.metals and noble gases
(3) the atomic mass of many elements not a whole number because B.An element may have isotopes with different numbers of neutrons.

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poncetmarina02 poncetmarina02 · Answer 2 · 2019-09-26T18:29:35+02:00

Answer:

The following are the correct answers to each question:

Q1:Option D. Vertical columns in the periodic table indicate groups and families

Q2:Option A. Metals and noble gases are families of elements.

Q3: Option B. The atomic mass of many elements are not whole numbers as an element may have isotopes with different numbers of neutrons.

Explanation:

Q1: The vertical columns in the periodic table are called groups or families as they all share similar chemical behavior. All the members of a family of elements have the same amount of valence electrons as well.

Q2: A chemical group of elements that share similar properties are made up of noble gases, and at the same time each chemical element can be classified as a metal or non-metal.

Q3: The atomic mass of many elements are not whole numbers as an element may have isotopes that always have the same number of electrons but different number of neutrons. Also the atomic mass is an average of all the atomic masses of the isotopes of a sample, which make it more possible for the number to be a decimal than a whole number.