If there's just some barium put in an aqueous solution, then it should be something like this.
It's a mixture of a solution and an insoluble solid, so the easiest way to go is through filtration. (Also, I'm assuming the barium is cut into very small chips.)
In a line, simply filter the solution using a folded filter paper in a funnel, collect the residue in a beaker or flask, rinse it with distilled water and let it dry. (Or simply filtering it could be enough, depending on how far your teacher wants you to go.)
Stuff needed:
>filter paper (for separating the solid from the solution)
>funnel (to hold the filter paper)
>beaker or flask (to hold the filtrate)
>distilled water (to rinse the solid)
>spatula (to scoop up the solid)
Procedure:
>Fold filter paper and line the funnel with it. Place the funnel in the flask or beaker.
>Pour solution in. Then add water (I think using tap water might be fine in this case, but you can use distilled water if you'd like) to wash out the container with the solution of any solid you may have not gotten in the first try. Alternatively, you could use a spatula to spoon it onto the filter paper.
>Once everything has been filtered, pour some distilled water on the residue on the filter paper to wash away the solution.
>Take out the filter paper, open it up and let it dry.
This can be used in real life in many occasions. For example, when you make tea, you need to filter the leaves out. Or when you cook the pasta, you put it in a sieve to separate the pasta from the water. Or when you fish using fishing nets, you "filter" the fish from the water.
Answer: 11.5 grams
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution
where,
Morality = 0.612 M
n= moles of solute
= volume of solution in ml = 100 ml
Now put all the given values in the formula of molarity, we get

Therefore, the mass of copper (II)nitrate required is 11.5 grams
Eight because an octet has 8 electrons and when it’s full it’s stable. If it’s not full, it’s constantly sharing or borrowing electrons.
An increase in the atmospheric concentrations of greenhouse gases produces a positive climate forcing, or warming effect. From 1990 to 2015, the total warming effect from greenhouse gases added by humans to the Earth's atmosphere increased by 37 percent.