Answer:
Groups
Explanation:
Elements with the same number of valence electrons are found in the same column(group) of the Periodic Table.
Answer:
177.1 L
Explanation:
The excersise can be solved, by the Ideal Gases Law.
P . V = n . R . T
In first step we need to determine the moles of gas:
We convert T° from, C° to K → 20°C + 273 = 293K
We convert P from mmHg to atm → 760 mmHg = 1atm
1Dm³ = 1L → 190L
We replace: 190 L . 1 atm = n . 0.082 . 293K
(190L.atm) / 0.082 . 293K = 7.91 moles.
We replace equation at STP conditions (1 atm and 273K)
V = (n . R .T) / P
V = (7.91 mol . 0.082 . 273K) / 1atm = 177.1 L
We can also make a rule of three:
At STP conditions 1 mol of gas occupies 22.4L
Then, 7.91 moles will be contained at (7.91 . 22.4) /1 = 177.1L
Answer:
7mL of sterile water is the initial amount of the concentrated solution is 3mL
Explanation:
In this problem, the vial must be <em>diluted </em>from 5mg/mL to 1.5mg/mL, that means the solution must be diluted:
5mg/mL / 1.5mg/mL = 3.33 times
If the initial amount of the drug in the vial is 3mL, the final volume must be:
10mL
That means the volume of water that should be added is:
10mL - 3mL:
<h3>7mL of sterile water is the initial amount of the concentrated solution is 3mL</h3>
Yes because some work harder than others to get their credit for developing the periodic table
