Chemistry Regent Exam-June 2014

Compared to the charge of a proton, the charge of an electon has

• a greater magnitude and the same sign
• a greater magnitude and the opposite sign
• the same magnitude and the same sign
• the same magnitude and the opposite sign

Which atom has the largest atomic radius?

• potassium
• rubidium
• francium
• cesium

Tags

NGSS.HS-PS1-1

In the wave-mechanical model of the atom, an orbital is defined as

• a region of the most probable proton location
• a region of the most probable electron location
• a circular path traveled by a proton around the nucleus
• a circular path traveled by an electron around the nucleus

When an excited electron in an atom moves to the ground state, the electron

• absorbs energy as it moves to a higher energy state
• absorbs energy as it moves to a lower energy state
• emits energy as it moves to a higher energy state
• emits energy as it moves to a lower energy state

Which polyatomic ion is found in the compound represented by the formula NaHCO₃?

• acetate
• hydrogen carbonate
• hydrogen sulfate
• oxalate

The atomic mass of magnesium is the weighted average of the atomic mass of

• all of the artificially produced isotopes of Mg
• all of the naturally occuring isotopes of Mg
• the two most abundant artificially produced isotopes of Mg
• the two most abundant naturally occuring isotopes of Mg

Which element has atoms that can form halide ions?

• iodine
• silver
• strontium
• xenon

Tags

NGSS.HS-PS1-2

Two forms of solid carbon, diamond and graphite, differ in their physical properties due to the differences in their

• atomic number
• crystal structures
• isotopic abundances
• percent compositions

Which quantity can be calculated for a solid compound, given only the formula of the compound and the Periodic Table of the Elements?

• the density of the compound
• the heat of fusion of the compound
• the melting point of each element in the compound
• the percent composition by mass of each eleement in the compound

Which terms identify types of chemical reactions?

• decomposition and sublimation
• decomposition and synthesis
• deposition and sublimation
• deposition and synthesis