Yes and no he said that all atoms of a given element are identical in mass and properties.
D = 0.2 g / ml = 0.2 g / cm³
For example, density of steel is 7.85 g / cm³.
Density of pure water is 1.0 g/cm³. An object which has a density < 1.0 g/cm³ will float in water.
Answer: Material that has a density of 0.2 g/ml ( 0.2 g/cm³ ) is good for making couch cushions.
Answer:
the answer is 2.75 but since that isn't an option I'd go with 1 because I just took a test with this question and it was the right answer.. hopefully that helps
The complete chemical reaction of aqueous Sodium sulfate and aqueous Barium nitrate is

The right side and the left side of the reaction have equal number of elements, therefore it is balanced.