Quiz 1

Which pair of nuclear symbols represent DIFFERENT isotopes of the SAME imaginary element, X?

• ²¹₉X and ²¹₁₀X

• ²¹₉X and ²¹₉X

• ²¹₉X and ²²₁₀X

• ²¹₉X and ²²₉X

An electron is promoted (excitation) to a higher energy level, due to quantum jump with an energy of 2.5 x 10^19 J. The electron is demoted to a lower energy level (relaxation) . PREDICT which response below is most likely to be true for a flame emitting light with an energy of 3.1 x 10^-19 J during a flame test.

• The potential energy being stored by the electron during the excitation phase DECREASED because the size of the quantum jump away from the nucleus DECREASED.

• The potential energy being stored by the electron during the excitation phase DECREASED because the size of the quantum jump away from the nucleus INCREASED.

• The potential energy being stored by the electron during the excitation phase INCREASED because the size of the quantum jump away from the nucleus INCREASED.

• The potential energy being stored by the electron during the excitation phase INCREASED because the size of the quantum jump away from the nucleus DECREASED.

A mass spectrometer sorts particles using degrees of deflection (shown below). A sample of copper is injected into a mass spectrometer. After the sample is vaporized and ionized, the ions 63Cu2+ and 65Cu2+ are detected. IDENTIFY the most accurate statement about the degree of deflection for each isotope inside the spectrometer during the analysis.

• 65Cu2+ deflects more due to having a larger mass with the same ionic charge.

• 63Cu2+ deflects more due to having a smaller mass with the same ionic charge.

• Both ions have the same degree of deflection due to having the same ionic charge of 2+.

• There is not enough information to determine which isotope deflects more.

A group of students studied the mass spectrum for a new element they want to name Takium, shown below. Which atomic mass below is MOST LIKELY to be the average atomic mass of this sample of Takium?

• 21.00 amu

• 21.32 amu

• 20.00 amu

• 20.18 amu

Which of the following BEST EXPLAINS why the effective nuclear charge (electron shielding and then attraction by the nucleus) experienced by valence electrons of a Cl atom is less than the effective nuclear charge experienced by valence electrons of an F atom?

• Valence electrons of a Cl atom experience more shielding from their nucleus than F atom valence electrons.

• The nucleus of a Cl atom contains more protons than the nucleus of an F atom.

• The mass of a Cl atom is greater than the mass of an F atom.

• Because the Cl atom is larger than the F atom, repulsions among electrons in the valence shell of Cl are less than the repulsions among electrons in the valence shell of F.

The complete PES graphs of two neutral elements, X (Carbon) and Y (Nitrogen), are provided. Which of the following statements comparing elements X and Y is BEST SUPPORTED by the data?

• Element X and Element Y have the same number of core electrons shielding the valence electrons from the positively charged nucleus.

• Element Y has a higher first ionization energy than Element X.

• Element X and Y have the same effective nuclear charge.

• Element Y has more stable isotopes than Element X.

The first five successive ionization energies for element X are listed in the table. On the basis of the data, element X is most likely to be...

• Mg

• Al

• Si

• P

A sample of NH3 is measured to be 102.37 g. How many MOLES of NH3 are in the sample?

• 0.63889 mol

• 6.0108 mol

• 5.7351 mol

• 1743.5 mol

A graph of first ionization energies of the elements is shown below. A student correctly observes that first ionization energy tends to increase as atomic number increases, but at regular intervals exhibits a significant drop between certain elements before increasing again. IDENTIFY the claim that is most relevant to the evidence the student cited from their observations first ionization graph.

• Electrons exist in different and separate energy levels in such a way that allows inner energy levels to shield the outermost energy level from the pull of attraction exhibited by the positive nucleus.

• Multiple stable isotopes exist of each neutral element due to having different numbers of neutrons with the same number of protons in the nucleus.

• Valence electrons repel one another in the valence shell with a non-contact pushing force due to having equivalent -1 charges.

• Atoms store energy through electrons quantum jumping to a new position, then release that stored energy as colored light.

Write the full electron configuration for a neutral atom of the element argon. (1 pt)