Atomic Structure

Atomic
Structure

Be ready to write in your STAAR booklet...

We'll add more detail to those tomorrow.
For today, we'll focus on the next two areas...

Multiple Choice

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

Multiple Choice

Students build a model of a lithium atom with different colored marbles. Based on the chart, which marbles should the students place in the nucleus of their lithium atom model?

• Blue and green

• Blue and red

• Green and red

• Blue, green, and red

Did you pay attention to the part about how to calculate neutrons...?

Fill in the Blanks

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?

Multiple Choice

Which table correctly identifies the charges of subatomic particles?

Remember, we get a lot of information from our periodic tables...

You have finished the review!
Now to start the practice...

Multiple Choice

Four elements are shown as they appear in the periodic table. Which statements makes an accurate comparison of some of these elements?

• An atom of scandium contains two more protons than an atom of vanadium

• An atom of chromium contains seven more protons than an atom of scandium

• An atom of titanium has fewer protons than an atom of vanadium but more protons than an atom of scandium

• An atom of chromium contains four more protons than an atom of scandium but only two more protons than an atom of titanium

Multiple Choice

The diagram shows a model of an atom. The model contains three different subatomic particles. Particles X and Y are inside the nucleus, and particle Z is outside the nucleus. Which statement best describes the charges on the particles in this model?

• Both particles X and Y have a positive charge, particle Z has a negative charge

• Both particles X and Y have a negative charge, particle Z has a positive charge

• Either particle X or particle Y has a positive charge, particle Z has a negative charge

• Either particle X or particle Y has a negative charge, particle Z has a positive charge

Fill in the Blanks

How many neutrons are in the nucleus of a potassium atom with a mass number of 39?

Multiple Choice

A student prepared diagrams to model atoms of two elements. Atoms of which two elements are represented by these models?

• Oxygen, O, and neon, Ne

• Fluorine, F, and neon, Ne

• Silicon, Si, and phosphorous, P

• Beryllium, Be, and boron, B

Multiple Choice

A chemist is identifying the elements present in a sample of seawater. What characteristic of an element's atoms always determines the element's identity?

• The number of protons

• The number of neutrons

• The location of valence electrons

• The number of valence electrons

Multiple Choice

Which statement correctly compares the masses of subatomic particles in an atom such as carbon?

• An electron has a greater mass than a proton

• A proton has about the same mass as an electron

• A proton has about the same mass as a neutron

• Neutrons, protons, and electrons have the same mass

Multiple Choice

An atom would become a different element if which characteristic changed?

• the number of protons

• the number of neutrons

• the number of energy levels

• the number of valence electrons

Multiple Choice

Which of these statements about the mass of subatomic particles is true?

• The mass of a proton is the same as the mass of an electron

• The mass of a neutron is the same as the mass of an electron

• The mass of a neutron is much greater than the mass of a proton

• The mass of a proton is much greater than the mass of an electron

Fill in the Blanks

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

Fill in the Blanks

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

Multiple Choice

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?

Multiple Choice

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 in the nucleus

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

Multiple Choice

Tin, Sn, is a soft white metal. it has a low melting point compared with other metals. Tin is widely used as a coating for cans of food. Which statement accurately describes atoms of tin?

• Tin atoms have 50 protons

• Tin atoms have five valence electrons

• Tin atoms have 119 neutrons

• Tin atoms have 68 electrons

Multiple Choice

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 than 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

Multiple Choice

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

• 18

• 19

• 20

• 39

Multiple Choice

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

Multiple Choice

The table below lists three characteristics of an atom of an element. An atom of which element is described by the data in the table?

• Radon (Rn)

• Cadmium (Cd)

• Rubidium (Rb)

• Astatine (At)

Multiple Choice

Which of the following best describes an electron?

• It has no charge and about the same mass as a proton

• It has a negative charge and much less mass than a proton

• It has a positive charge and much more mass than a neutron

• It has a negative charge and about the same mass as a neutron

Multiple Choice

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

• 72 protons, 178 neutrons, 106 electrons

• 72 protons, 106 neutrons, 72 electrons

• 178 protons, 250 neutrons, 72 electrons

• 106 protons, 72 neutrons, 106 electrons

Multiple Choice

Atoms of which two elements have a combined total of 23 protons?

• Sodium, Na, and magnesium, Mg

• Boron, B, and carbon, C

• Copper, Cu, and zinc, Zn

• none of these

Multiple Choice

An atom has 25 protons, 30 neutrons, and 25 electrons. What is the charge of the atom's nucleus?

• +25

• +30

• -25

• -30