NY Regents Chemistry Exam June 2023 Questions 66-69
Several elements are considered endangered because there is a risk of these elements becoming unavailable for commercial uses in the next 100 years. Helium, zinc, gallium, indium, and tellurium are included in the list of these endangered elements.
66 Identify the three endangered elements listed in the passage that are classified as metals.
Solution: Metals are to the left of the staircase on the Periodic Table. Gallium, indium and zinc are metals.
67 Explain, in terms of electrons, why gallium and indium have similar chemical properties.
Solution: Atoms of elements in the same group have similar chemical properties because they have the same number of valence electrons.
68 Compare the density of a sample of helium at STP with the density of a sample of tellurium at STP.
Solution: Table S on the Reference Table lists all the elements with their densities. You can look up the densities and compare them. Tellurium is more dense than helium.
69 Explain, in terms of electron shells, why the atomic radius of an atom of indium is greater than the atomic radius of an atom of gallium when both atoms are in the ground state.
Solution: The more electron shells an atom has, the bigger its atomic radius is. Indium has more shells than gallium
Prepare for the Chemistry Regents Exam: HERE
Contact us for Online Expert Chemistry Tutoring: HERE