Atoms, Ions, Bonds, Chemical Reactions

What is the charge on an electron?

A molecule is:

Compound (Chemistry)?

A neutral atom that gains or loses electrons becomes _

What is not conserved in an isolated chemical reaction?

How many electrons does a neutral potassium atom have?

Neutrons have what charge?

​99.94% of the mass (energy) of an atom is contained in the _.​

What is a transition from a solid to a gas called?

Also known as Heat Energy. It is the vibration and movement of atoms and molecules.

To become a negative ion, an atom must ____________.

Physical change or chemical reaction?

Elements in vertical columns of the periodic table have similar properties, they are called _.

Which subatomic particles are located inside the nucleus of an atom?

Which is not a state of matter?

How many oxygen atoms are there in a water molecule (H₂O)?

Physical change or chemical reaction?

Any extended structure with an orderly arrangement of atoms.

Protons have what charge?

Chemical bonds result from

What atomic number is helium (He)?

What is the evidence of reaction in the picture below?

Rows in the periodic table are called _.

Physical change or chemical reaction?

4Fe + 3 O₂ → _ Fe₂O₃

To become a positive ion, an atom must ___________ .

The number of protons an atom contains is identified by the ____ ____ on the periodic table.

When a hydrocarbon like wax, natural gas or petroleum is burned completely, the products are _.

What is the most abundant element (by mass) found on Earth?

An atom is electrically neutral when it contains equal numbers of

In a chemical reaction, atoms