Question

1. the periodic table is organized by increasing:

a) atomic number
b) atomic mass
c) density
d) reactivity

1. each horizontal row on the periodic table is called a:

a) group
b) family
c) period
d) block

1. each vertical column on the periodic table is called a:

a) period
b) group
c) line
d) element

1. the number of protons in an atom is called the:

a) mass number
b) atomic number
c) isotope
d) valence

1. the periodic table was first created by:

a) albert einstein
b) dmitri mendeleev
c) isaac newton
d) marie curie

1. the elements are arranged in order of:

a) color
b) atomic mass
c) atomic number
d) melting point

Explanation:

1. The periodic table is organized by increasing atomic number. Atomic number is the number of protons in an atom's nucleus and determines the element's identity.
2. Each horizontal row on the periodic table is called a period. Periods show trends in properties as you move across them.
3. Each vertical column on the periodic table is called a group (or family). Elements in the same group have similar chemical properties.
4. The number of protons in an atom is called the atomic number. It uniquely identifies an element.
5. The periodic table was first created by Dmitri Mendeleev. He arranged elements based on atomic mass and predicted properties of undiscovered elements.
6. The elements are arranged in order of atomic number. This is the modern basis of the periodic table.

Answer:

1. A. Atomic number
2. C. Period
3. B. Group
4. B. Atomic number
5. B. Dmitri Mendeleev
6. C. Atomic number