During all chemical reactions, the mass of the products is never equal to the mass of the reactants.
- FALSE
Mass is sometimes lost in chemical reactions.
- FALSE
The Law of Conservation of Mass states that mass is not conserved.
- FALSE
<span>This is due to the fact that the air pressure in that certain section of Earth’s atmosphere decreased. As density of gas particles decreases as air pressure decreases. Therefore, density of gas particles and air pressure have a direct relationship. An increase in air pressure would then effect to an increase in gas particles. </span>
Answer:
A. Because they are compounds, they cannot be pure substances.
Explanation:
The false statement from the given choices is that because they are compounds they cannot be pure substances. In fact, because they are compounds they are pure substances.
Pure substances are made up of elements and compounds and they have the following properties:
- All parts are the same throughout
- Composition is definite
- They cannot easily be separated or broken
- Separation by physical method is not easy
- They have unique sets of physical and chemical properties.
The total charge of a compound must be zero. So the Y ion has charge of -2. Then the charge of X ion+(-2)*2=0. So the charge of X ion is +4.
