Choose the INCORRECT Statement

question 91

Multiple Choice

Choose the INCORRECT statement.

• A) Among the methods to separate the lanthanides are fractional precipitation and solvent extraction.
• B) Because the properties of the lanthanides are so similar, separation must be done in a series of repetitive steps.
• C) Lanthanides are reactive metals, that is they liberate H₂ from acids.
• D) The 4f electrons play a major role in chemical bonding.
• E) The pure lanthanide metals can be produced by electrolytic reduction from the +3 oxidation state.

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Definitions:

Objective Lens

The part of a microscope or telescope that is closest to the object being observed, focusing light and creating an initial image.

Oil-Immersion Lens

A microscope lens designed to be used with a drop of oil between the lens and the slide, improving resolution by reducing light refraction.

Fine Focus Knob

A control mechanism on microscopes used to make precise adjustments to the focus, sharpening the image of the specimen.

Coarse Focus Knob

A control mechanism on microscopes used for making large adjustments in focus, allowing for the initial focusing of the microscope lens on the specimen.