The compound sodium sulfate is made of sodium ion and sulfate ion.
The formula can be written as Na₂SO₄.
The cation present in this compound is Na⁺ and the anion is SO₄²⁻.
The compound barium sulfate is made of barium ion and sulfate ion.
The formula can be written as BaSO₄.
This compound contains the cation Ba²⁺ and anion SO₄²⁻.
From the above , we can see that both the compounds have common anion which SO₄²⁻
So, the sulfate, SO₄²⁻ is the common ion when sodium sulfate is added to a solution of barium sulfate
D.
Gastropods live in every conceivable habitat
Answer: The empirical formula is 
Explanation:
If percentage are given then we are taking total mass is 100 grams.
So, the mass of each element is equal to the percentage given.
Mas of H = 1.8 g
Mass of S = 56.1 g
Mass of O = 42.1 g
Step 1 : convert given masses into moles.
Moles of H =
Mass of S =
Moles of O=
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For H =
For S =
For O =
Converting to whole number ratios
The ratio of H: S: O= 2: 2: 3
Hence the empirical formula is 
Answer:
Pasteurization involves heating liquids at high temperatures for short amounts of time. Pasteurization kills harmful microbes in milk without affecting the taste or nutritional value (sterilization= all bacteria are destroyed).
Explanation: