Quarterly 2 Review Quizizz

Energy flows into an atom and excites an electron. The electron goes from its lower energy state (________) to a higher energy state (________). As the electron falls back down to the original energy state, light is produced.

• excited, ground

• ground, excited

Answer explanation

The lower energy level is called the ground state--this is where the electron is located originally before any energy is put into the atom.

The higher energy level is called the excited state--where the electron jumps to. It eventually has to fall.

Tags

NGSS.HS-PS1-2

What element have the lowest electronegativity?

• Francium

• Rubidium

• Magnesium

• Chlorine

Answer explanation

Nonmetals have high electronegativity--so you can immediately get rid of Chlorine as an option.

Francium, Rubidium, Magnesium are all nonmetals so you know their electronegativity will be low--you just need to figure out what is the lowest. The more electrons/electron shells an element has--the lower the electronegativity.

Francium has 87 (7 levels), Rubidium has 37 (5 levels), Magnesium has 12 (3 levels).

Which element has the smallest atomic radius?

• Silicon

• Phosphorous

• Sulfur

• Chlorine

Answer explanation

As you go from left to right (metals to nonmetals) the atomic radius DECREASES. This is because as you go from left to right, there are more protons in the nucleus. These protons have a positive charge and pull the electrons closer to the nucleus--making the atomic radius smaller.

Which of the following atoms are LEAST likely to form a compound?

• Sodium (Na) and Chlorine (Cl)

• Calcium (Ca) and Iodine (I)

• Sulfur (S) and Chlorine (Cl)

• Helium (He) and Xenon (Xe)

Answer explanation

Sodium + Chlorine and Calcium + Iodine are metals + nonmetals so that is an ionic compound.

Sulfur+Chlorine are nonmetal + nonmetal so that is a molecular (covalent) compound.

Helium+Xenon are both noble gasses, so they will not form a compound.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

How can you tell that elements would react the same?

• They are in the same group (vertical column).

• They are in the same period (horizontal row).

Tags

NGSS.HS-PS1-2

How does strontium (Sr) obey the octet rule

• The number of electrons doesn't change.

• It gains electrons.

• It gives up electrons.

• Strontium doesn't obey the octet rule, silly goose.

Answer explanation

Strontium is a metal and all metals give up electrons to obey the octet rule.

Nonmetals gain electrons/share electrons to obey the octet rule.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What do all of the elements below have in common?

• They are all metals.

• They are all nonmetals.

• They all have 4 valence electrons.

• They have the same number of electrons.

Answer explanation

These elements are a mixture of metals, nonmetals, and post-transition metals.

Each has a different atomic number, therefore a different number of electrons.

They all have 4 valence electrons because they're in the same group.

Tags

NGSS.HS-PS1-1

What are properties of ionic compounds?

• low melting point and conducts electricity as a solid.

• high melting point and conducts electricity when dissolved in water.

• low melting point and conducts electricity when dissolved in water.

• high melting point and conducts electricity as a solid.

Arrange the following wavelengths from highest frequency to lowest frequency: microwave, x-ray, gamma, visible.

• microwave, x-ray, gamma, visible

• gamma, x-ray, visible, microwave

• visible, gamma, x-ray, microwave

• microwave, visible, x-ray, gamma

Answer explanation

The spectrum goes from low frequency (left) to high frequency (right).

Tags

NGSS.HS-PS4-1

Which Lewis Dot Diagram would represent Iodine?

• 
• 
• 
• 

Answer explanation

Iodine is in group 17, which is group 7 when drawing valence electrons.

Tags

NGSS.HS-PS1-1