Physical Science 1st Semester Review

Front

What is the structure of BF3?

Back

BF3 has a trigonal planar structure with boron at the center and three fluorine atoms at the corners of an equilateral triangle.

Front

What is the correct formula for silicon tetrafluoride?

Back

The correct formula is SiF4.

Front

How is an atom best described?

Back

An atom is best described as a positive nucleus surrounded by a cloud of negative charges.

Front

Convert 35,400 mg to grams.

Back

35,400 mg is equal to 35.4 g.

Front

What is the correct Lewis structure for water (H2O)?

Back

The correct Lewis structure for water shows the oxygen atom in the center with two hydrogen atoms bonded to it, and two lone pairs of electrons on the oxygen.

Front

What is the definition of a molecule?

Back

A molecule is a group of two or more atoms bonded together, representing the smallest fundamental unit of a chemical compound.

Front

What is the difference between an element and a compound?

Back

An element is a pure substance made of only one type of atom, while a compound is a substance formed when two or more different types of atoms bond together.

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction.

Front

What is the pH scale?

Back

The pH scale measures the acidity or basicity of a solution, ranging from 0 (very acidic) to 14 (very basic), with 7 being neutral.

Front

What is the definition of an ion?

Back

An ion is an atom or molecule that has gained or lost one or more electrons, resulting in a net electrical charge.