Answer:
Group 18th
Explanation:
The group 18th of periodic table which is composed of Noble gases mainly was missing from the Mendeleev's periodic table. The reason for this is that Noble gases are least reactive, therefore, it was difficult to predict such elements which do not react with other elements.
Answer:
14
Explanation:
mass number = protons + neutrons
Answer : The mass in grams of calcium sulfate is 0.16 grams.
Explanation :
Molarity : It is defined as the number of moles of solute present in one litre of solution.
Formula used :

Solute is, 
Given:
Molarity of
= 0.0025 mol/L
Molar mass of
= 136 g/mole
Volume of solution = 485 mL
Now put all the given values in the above formula, we get:


Thus, the mass in grams of calcium sulfate is 0.16 grams.
The answer has to be either CO2 or mg. But i am not sure which one
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