PERIODIC TABLE [dchemlc]

The Group O elements are known as the noble gases because they are almost completely unreactive. What is the reason for this?

• because the outer shell is full, and so there is no tendency to lose, gain or share electrons in a chemical reaction

• because the outer shell already has 7 electrons and cannot take anymore

• because it has no electrons to lose or gain

• because all elements in group 0 are gases

Answer explanation

give another name for group 1 elements

• alkali metals

• alkali earth metals

• halogens

• noble gases

Answer explanation

Some of the groups have names,

Group 1 is the alkali metals,

Group 7 is the halogens and Group O is the noble gases.

how many electrons can be found in Phosphorous?

• 15

• 3

• 5

• 18

Answer explanation

# Most Periodic Tables have two numbers against each symbol. The atomic number will always be the smaller number.

# the number of protons in an atom is equal to the atomic number.

# the number of electrons in an atom is equal to the number of protons.

how many electrons can the second energy level of atoms hold?

• 8

• 18

• 2

• 18

Answer explanation

The electrons move around the nucleus in a series of levels called energy levels or shells.

Each energy level (shell) can only hold a certain number of electrons.

Lower energy levels are always filled before higher ones.

The lowest energy level is the closest one to the nucleus.

The arrangement of electrons in an atom is called its ___________.

what is the electronic configuration of potassium?

Answer explanation

which of the following elements do not belong to group 5?

• 
• 
• 
• 

Answer explanation

Elements in the same group in the Periodic Table have the same number of electrons in their outer shell.

The number of electrons in the outer shell is the same as the group number for Groups 1 to 7.

the element livermorium can be found in the 7th period of the periodic table. How many occupied shells does it have?

• 7

• 6

• 116

• 8

Answer explanation

The period number gives the number of occupied shells or the highest occupied shell.

which of the following is not true about the periodic table?

• Elements in the same group have the same number of occupied shells

• Elements in the same group have the same number of electrons in their outer shell

• Elements in the same group have similer chemical properties

• The number of electrons in the outer shell is the same as the group number for Groups 1 to 7.

Answer explanation

The period number gives the number of occupied shells or the highest occupied shell.

which of the following statements are false about metals and non-metals?

• Metals generally form acidic oxides while non-metals generally form basic oxides

• Metals conduct electricity and non-metals do not generally conduct electricity

• Metals are malleable and ductile but non-metals tend to be brittle

• Metals are good conductors of heat but non-metals are poor conductors of heat

Answer explanation

Metals generally form basic oxides.

Non-metals generally form acidic oxides.