Physical Science Midterm

Front

What does the name 'dinitrogen tetroxide' indicate about the compound's composition?

Back

It contains two nitrogen atoms and four oxygen atoms.

Front

Which substance is a gas at 45°C?

Back

Methane.

Front

What happens to the speed of molecules when a substance changes from a gas to a liquid?

Back

The speed of the molecules decreases, because they have lower kinetic energy in the liquid state.

Front

How many electrons does a neutral atom of Beryllium have?

Back

4.

Front

Which pair of elements has similar chemical properties according to the periodic table?

Back

Aluminum (Al) and Gallium (Ga).

Front

Define a covalent compound.

Back

A chemical compound formed by the sharing of electrons between atoms.

Front

What is kinetic energy?

Back

The energy that an object possesses due to its motion.

Front

What is the significance of the periodic table in chemistry?

Back

It organizes elements based on their atomic number, electron configurations, and recurring chemical properties.

Front

What is the difference between a gas and a liquid in terms of molecular arrangement?

Back

In a gas, molecules are far apart and move freely; in a liquid, molecules are closer together and can slide past one another.

Front

What is the chemical formula for methane?

Back

CH₄.