The lines in the emission spectrum of hydrogen result from __________.

• electrons given off by hydrogen as it cools

• decomposing hydrogen atoms

• electrons given off by hydrogen when it burns

• energy given off in the form of visible light when an electron moves from a higher energy state to a lower energy state

Tags

NGSS.HS-PS4-3

Which of the subshells below does not exist ?

• 2p

• 2s

• 2d

• all of the above

The first ionization energies of the elements __________ as you go from left to right across a period of the periodic table, and __________ as you go from the bottom to the top of a group in the table

• increase, increase

• increase, decrease

• decrease, increase

• decrease, decrease

• are completely unpredictable

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which ion in the isoelectronic series below has the smallest radius in a crystal?

• O^2-

• N^3-

• Na⁺

• Al³⁺

• F^-

An example of an electron configuration of a transition metal is __________.

• 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s¹

• 1s² 2s² 2p⁶ 3s² 3p⁵

• 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁸

• 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶

• 1s² 2s² 2p⁴ 3s¹

Tags

NGSS.HS-PS1-1

Of the choices below, which gives the order for first ionization energies?

• Cl > S > Al > Ar > Si

• S > Si > Cl > Al > Ar

• Al > Si > S > Cl > Ar

• Cl > S > Al > Si > Ar

• Ar > Cl > S > Si > Al

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Four isotopes of lead include lead-204, lead-206, lead-207, and lead-208.  The average atomic mass of lead is 207.2.  Which isotope of lead is likely to be the most abundant.

• 204
• 206
• 207
• 208

Tags

NGSS.MS-PS1-1

What are valence electrons?

• electrons on the first orbital always
• nucleus
• the outermost shell
• the number of electrons on the outermost orbital

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What kind of mixture is a combination of substances that has uniform composition and appearance?

• colloid

• heteregenous

• homogeneous

• suspension

Why does ionization energy decrease going down a group?

• Adding more energy levels makes the ve- further from the nucleus
• There are more valence electrons in the outer shell
• There are more protons  in the nucleus
• There are less protons in the nucleus

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2