F2024 Final Chemistry Review

Front

What are subscripts in a chemical formula?

Back

Subscripts are the small numbers written to the lower right of an element symbol in a chemical formula that indicate the number of atoms of that element in a molecule.

Front

How many atoms of nitrogen are in the compound N2O4?

Back

There are 2 atoms of nitrogen in the compound N2O4.

Front

True or False: Isotopes of an element have different chemical properties.

Back

False. Isotopes of an element have the same chemical properties because they have the same number of protons.

Front

What is the balanced equation for the combustion of B2H6?

Back

B2H6 + 3O2 → 2HBO2 + 2H2O.

Front

How do you calculate the mass of O2 needed to burn a given mass of B2H6?

Back

Use stoichiometry based on the balanced equation to find the molar ratio and convert grams of B2H6 to grams of O2.

Front

What is the formula for strontium hydroxide?

Back

The formula for strontium hydroxide is Sr(OH)2.

Front

What is the definition of a chemical reaction?

Back

A chemical reaction is a process that leads to the transformation of one set of chemical substances to another.

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 are oxidation numbers?

Back

Oxidation numbers are assigned to atoms in a compound to indicate the distribution of electrons among them.

Front

What is the difference between an ionic bond and a covalent bond?

Back

An ionic bond is formed by the transfer of electrons from one atom to another, while a covalent bond is formed by the sharing of electrons between atoms.