Front

What is the percentage of Oxygen gas in the air?

Back

21%

Front

True or False: Air is a mixture.

Back

True

Front

Why do odors have different smells even if they contain the same atoms?

Back

The arrangement and the amount of atoms are different.

Front

Which of the following is an element: N2, O2, He, or All of them?

Back

All of them are!

Front

What activity demonstrated that gases can be distinguished even though they are colorless and odorless?

Back

Emission Spectra.

Front

Define 'mixture' in the context of air.

Back

A mixture is a combination of two or more substances where each retains its own properties.

Front

What are the main components of air?

Back

Nitrogen (78%), Oxygen (21%), and other gases (1%).

Front

Explain the concept of 'emission spectra'.

Back

Emission spectra are the spectrum of light released from excited atoms, used to identify different gases.

Front

What is the significance of atomic arrangement in chemistry?

Back

The arrangement of atoms determines the properties and behavior of a substance.

Front

What is the difference between an element and a compound?

Back

An element is a pure substance made of one type of atom, while a compound is made of two or more different types of atoms chemically bonded.