Density = mass/volume
Density = 81g/0.9cm³
Density = 90g/cm³
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Answer:
Use a 10 mL pipet and a 50 mL volumetric flask, <em>twice</em>
Explanation:
Given those conditions, in order to have a solution that is 25 times less concentrated that the one previously prepared, we would need two dillution steps, as suggested by the problem.
If we take an aliquot of 10 mL and dilute it to a final volume of 50 mL, we prepare a solution that is 5 times less concentrated. And if we then take again an aliquot of 10 mL of that dilluted solution and dilute it to a final volume of 50 mL, we would have a solution 25 (5 times 5) times less concentrated than the original one.
In order to verify, we can calculate the resulting concentration and compare it with the original one:

Thus we can see that the obtained concentration is in fact 25 times lower than the original concentration.
As you know, an element'svalence electrons are simply theelectrons located on the outermost energy level, i.e. on thehighest occupied energy level. Therefore, you can say that anelement located in group 5A has 5 electrons on its highest occupied energy level. so the answer would be c.5
Because the sun is a sustainable source of energy that can be used to power homes and businesses globally.
Answer:
179g
Explanation:
Molar ratio for Copper : Lithium is
1:2
If there are 89.5g of copper
Grams for Lithium= 89.5 × 2 = 179g of Lithium