Periodicity

There is no particular trend in melting point across a period. Because there are different bonds in metals and non-metals. Usually, metals have higher melting points while non-metals have very ............... melting points

Melting point of Potassium (K) is ............ than that of Sodium (Na)

Tags

NGSS.HS-PS1-1

Melting point of Calcium (Ca) is ............ than that of Potassium (K)

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Metallic character is an ability to give electrons. Metallic character increases down the group. For example in group 17, Fluorine (F) and Chlorine (Cl) are gases while Iodine (I) is a shiny solid, like a metal. In group 16 ...

• Oxygen is a non metal, while Sulfur is metal

• Oxygen is a non metal, while Polonium is metal

• Sulfur is a non metal, while Oxygen is metal

• Polonium is a non metal, while Oxygen is metal

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Metallic character has an opposite trend to electronegativity. Metals are usually at the bottom left and non-metals are at the top right. Considering that, metallic character will .................. across a period, from left to right.

Choose correct keywords.

Melting point in alkali metals, group 1 elements, ................... down the group while in group 7 it will .......................

• increase, increase

• increase, decrease

• decrease, increase

• decrease, decrease

According to the Periodic Table of the Elements, which set of elements has SIMILAR properties?

• H, C, I

• O, S, Se

• P, S, Cl

• Na, Ca, Ba

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What did Mendeleev observe when he arranged the 63 known elements by increasing atomic mass on the periodic table?

• A repetition pattern occurs in chemical and physical properties of elements throughout the periodic table.

• An atomic weight  correspond (match or agree almost exactly) to the existing abundance (amount) of each element in the universe

• The number of neutrons and protons increased by one through the periodic table.

Elements that are in family groups have similar properties. Which element would have similar properties as  Fluorine (F)?

• oxygen (O)

• sulfur (S)

• potassium (K)

• chlorine (Cl)

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

The atoms in a family group on the periodic table all have similar properties because

• they have the  same abbreviation

• they have same number of energy levels around the nucleus

• they have same number of electrons around the nucleus

• they have same number of electrons in the outer energy level or section of the atom

Tags

NGSS.HS-PS1-1