Atomic Structure (8.5A) STAAR Practice

The atomic number of krypton is 36. If the mass number of a krypton atom is 84, which table shows the number of subatomic particles inside and outside the nucleus of the krypton atom?

• 
• 
• 
• 

Tags

NGSS.MS-PS1-1

Which statement accurately describes the atoms of a specific element?

• An Indium, In, atom contains 115 protons inside the nucleus and 49 neutrons outside the nucleus

• A scandium, Sc, atom contains 45 electrons outside the nucleus and 21 neutrons inside the nucleus

• An aluminum, Al, atom contains 27 electrons and 27 protons inside the nucleus

• A zinc, Zn, atom contains 30 protons inside the nucleus and 30 electrons outside the nucleus

Tags

NGSS.MS-PS1-1

Which statement correctly describes the location and charge of the electrons in an atom?

• The electrons are inside the nucleus and have no charge

• The electrons are outside the nucleus and have no charge

• The electrons are inside the nucleus and have a negative charge

• The electrons are outside the nucleus and have a negative charge

What is the total number of protons, neutrons, and electrons in a cadmium, Cd, atom that has a mass number of 112?

Hint: Use APEMAN

• 48

• 64

• 160

• 208

What is the difference between the number of electrons in an atom of selenium, Se, and the number of electrons in an atom on aluminum, Al?

• 34

• 13

• 21

• 47

How many protons, neutrons, and electrons are present in an atom of hafnium, Hf, with a mass number of 178?

Hint: Complete APEMAN

• 72 protons, 178 neutrons, 106 electrons

• 72 protons, 106 neutrons, 72 electrons

• 178 protons, 250 neutrons, 72 electrons

• 106 protons, 72 neutrons, 106 electrons

Tags

NGSS.MS-PS1-1

An atom of a certain element has 36 protons, 36 electrons, and a mass number of 84. At room temperature this element is a very stable gas. How many neutrons are in this atom?

Hint: Use APEMAN

• 36

• 48

• 38

• 72

In the early 1900s many scientists thought that an atom consisted of a positive substance with negative charges scattered throughout the substance. Then Ernest Rutherford completed an experiment that changed the concept of an atom. His discovery led to the understanding that an atom consists mostly of empty space with--

• protons orbiting a dense nucleus made of electrons and neutrons

• electrons orbiting a dense nucleus made of protons and neutrons

• neutrons and protons orbiting a cloud of electrons

• electrons and protons orbiting a cloud of neutrons

Tags

NGSS.HS-PS1-8

A model of a beryllium atom is shown.

What types of particles are found in the cloud surrounding the atom's nucleus?

• positively charged particles and negatively charged particles

• negatively charged particles only

• neutral particles and positively charged particles

• positively charged particles only

Tags

NGSS.MS-PS1-1

What is the mass number of a potassium (K) atom that has 20 neutrons?

Hint: Use APEMAN

• 18

• 19

• 20

• 39