I believe the answer is A the 1st one
Answer:
[CaCl₂] = 1.32 M
Explanation:
We know the volume of solution → 0.30 L
We know the mass of solute → 44 g of CaCl₂
Let's convert the mass of solute to moles.
44 g . 1 mol / 110.98 g = 0.396 moles
Molarity (mol/L) → 0.396 mol / 0.3 L = 1.32 M
17) 8.4 / 20 x 100
18) 20 . 0.5150
19) 6,50% because (as you said) the law of definite proportions states that regardless of the amount, a compound is always composed of the same elements in the same proportion by mass
Explanation:
Scandium has atomic number of 21. This means that in it's neutral state its going to have 21 electrons.
a) The full electronic configuration is given as;
1s2 2s2 2p6 3s2 3p6 3d1 4s2
The final electron is placed in the d orbital. The shell is 3d
(b) When scandium has a charge if +1, it has lost an electron. The total number of electrons would now be 21-1 = 20
The electronic configuration would be given as;
1s2 2s2 2p6 3s2 3p6 4s2
The electron in the 3d orbital would be removed.
Three that is the answer to your question
