Answer:
Freezing and Melting (Fusion)
Explanation:
Answer: 35.4 grams
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

where,
Molality = 2.65
n= moles of solute =?
= volume of solution in ml = 445 ml
Putting in the values we get:


Mass of solute in g=
Thus 35.4 grams of
is needed to prepare 445 ml of a 2.65 m solution of
.
Answer:
SeCl₆ < SeF₂ < SeO₂
Explanation:
(A) SeO₂
The central atom has 2 bond pairs and 1 lone pair. The molecule is bent shaped which has an angle of 120°.
(B) SeCl₆
The central atom has 6 bond pairs and 0 lone pair. The geometry is octahedral in which the equatorial bonds has an angle of 90° and axial bond has an angle of 90°.
(C) SeF₂
The central atom has 2 bond pairs and 2 lone pairs. The geometry is bent shape which has an angle of approximately 105.5°.
The order is:
<u>SeCl₆ < SeF₂ < SeO₂</u>
A is your answer.
On the periodic table the atomic number is the number of protons inside the nucleus.