atomic structure

Modern Atomic Theory states that:

• electrons exist around the nucleus an move like planets around the sun

• electrons move really fast and are small compared to the rest of the atom and have no path.

• electrons are found in a cloud that represents the most probable area to find them.

• electrons are the largest subatomic particle

Which image shows light being given off?

• Image A because energy is absorbed then given off

• Image A because energy is released then abosorbed

• Image B because energy is absorbed then given off

• Image B because energy is released then abosorbed

What is the mass number of an element with 6 protons, 6 electrons and 8 neutrons?

• 12

• 14

• 22

• 2

Which of the following is true of Mg-25?

• It is Magnesium because it has 25 neutrons

• It is Magnesium because it has 12 protons

• It is Magnesium because it has 25 protons

• It is Magnesium because it has a mass of 25

An unknown element,X,has two isotopes. X-35 has an actual mass of 34.9689 and X-37 has a mass of 36.9659 u. In any sample of chlorine atoms, 75.771% will be X-35 and 24.229% will be X- 37. What is the average mass? (calculate)

• 36.9

• 40.1

• 37.0

• 35.5

Oxygen has three isotopes: O-16, O-17, and O-18. Which one is the most abundant?

• O-16

• O-17

• O-18

How many neutrobns does Ca-41 have?

• 41 because neutrons = mass - protons

• 20 because neutrons = the atomic number

• 21 because neutrons = mass-protons

• 41 because neutrons equals the number after the dsah

Answer explanation

How many electrons does F-18 have?

• 18

• 9

• 10

• 8

What atom matches this electron configuration?
1s²2s²2p⁶3s²3p⁶4s²3d¹⁰

• Zinc
• Copper
• Nickel
• Germanium

Identify the Electron Configuration for Aluminum (Al)

• 1s² 2s² 2p⁶ 3s² 3p¹
• 1s² 2s² 2p⁶ 3s² 3p³
• 1s² 2s² 2p⁶ 3s² 4p¹