Water and salt are compounds made of the combination of more than one type of atom. Which statement is false?

A. Because they are compounds, they cannot be pure substances.
B. Both compounds are considered pure substances.
C. These compounds have specific physical properties that never
change.
D. These compounds have distinct chemical properties.

Please explain.

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:

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles

the solar system used to have much dust particles option no d