9th grade test

Front

What is the atomic weight of oxygen?

Back

15.9994

Front

How many hydrogen atoms are there in C2H6?

Back

6

Front

What is the atomic number of Nitrogen?

Back

7

Front

If an atom has 3 electrons, how many protons does it have?

Back

3

Front

Which of the following is not a sign of a chemical change?

Back

Changing state

Front

Define atomic weight.

Back

The average mass of an atom of an element, measured in atomic mass units (amu).

Front

What is the significance of atomic number?

Back

It determines the identity of an element and the number of protons in the nucleus.

Front

What is a chemical change?

Back

A process where substances combine or break apart to form new substances.

Front

What are the signs of a chemical change?

Back

Releasing bubbles, production of new materials, releasing heat.

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.