Reactivity Trends in the Periodic Table

The video explains how reactivity in the periodic table varies based on atomic radius and electron configuration. Reactivity increases down groups 1 and 2 due to larger atomic radii, making it easier for atoms to lose electrons. Conversely, reactivity increases up group 17, as smaller atomic radii allow atoms to gain electrons more easily. Fluorine is highlighted as the most reactive element in group 17 due to its small size and high electronegativity. The video also discusses how reactivity trends across periods, with elements on the right side of the table gaining electrons more easily as atomic radius decreases.

Why does reactivity increase down groups 1 and 2 of the periodic table?

• Because the number of electron shells decreases.

• Because the number of valence electrons increases.

• Because the atomic radius increases.

• Because the atomic radius decreases.

What makes cesium extremely reactive?

• It has a small atomic radius.

• It has a low number of electron shells.

• It has a large atomic radius.

• It has a high number of valence electrons.

Why is fluorine highly reactive despite not having one or two valence electrons to give away?

• It has a small atomic radius and needs to gain one electron.

• It has many electron shells.

• It has a full valence shell.

• It has a large atomic radius.

What is the trend in reactivity for group 17 elements?

• Reactivity increases upwards in the group.

• Reactivity decreases down the group.

• Reactivity remains constant down the group.

• Reactivity increases down the group.

Which group of elements are known as the halogens?

• Group 16

• Group 18

• Group 17

• Group 15

Why is fluorine more reactive than nitrogen or oxygen?

• Fluorine has a smaller atomic radius and a stronger attraction to the nucleus.

• Fluorine has fewer valence electrons.

• Fluorine has more electron shells.

• Fluorine has a larger atomic radius.

What happens to the atomic radius as you move along a period from left to right?

• It increases.

• It decreases.

• It remains the same.

• It fluctuates.

How does adding electrons to the valence shell affect the atomic radius?

• It makes the atomic radius fluctuate.

• It has no effect on the atomic radius.

• It makes the atomic radius smaller.

• It makes the atomic radius larger.

What is the general trend of reactivity for elements on the left side of the periodic table?

• Reactivity increases to the left and downwards.

• Reactivity increases to the right and upwards.

• Reactivity decreases to the left and downwards.

• Reactivity remains constant.

Why do noble gases in group 18 typically not react?

• They have many electron shells.

• They have a small atomic radius.

• They have a large atomic radius.

• They have a full valence shell.