Answer:
Krypton
Explanation:
When Selenium forms an ion, it is trying to become krypton which is a noble gas.
Selenium belongs to the oxygen group on the periodic table. In this group, the atoms prefers to gain two electrons to complete their octet. When selenium gains two electrons, its octet is complete.
This will make the atom resemble krypton on the periodic table of elements.
This structure which is an octet confers a special stability on the element.
There are two meanings to the word "Distal"
Anatomy
- situated away from the center of the body or from the point of attachment.
Geology
2. relating to or denoting the outer part of an area affected by geological activity.
Basis: 1 L of the substance.
(1.202 g/mL) x (1000 mL) = 1202 g
mass solute = (1202 g) x 0.2 = 240.2 g
mass solvent = 1202 g x 0.8 = 961.6 g
moles KI = (240.2 g) x (1 mole / 166 g) = 1.45 moles
moles water = (961.6 g) x (1 mole / 18 g) = 53.42 moles
1. Molality = moles solute / kg solvent
= 1.45 moles / 0.9616 kg = 1.5 m
2. Molarity = moles solute / L solution
= 1.45 moles / 1 L solution = 1.45 M
3. molar mass = mole solute / total moles
= 1.45 moles / (1.45 moles + 53.42 moles) = 0.0264
Answer:
Explanation:
<u>1) Convert the mass of water into number of moles</u>
- Molar mass of water: 18.015 g/mol
- Number of moles, n = mass in grams / molar mass
n = 255 g / 18.015 g/mol = 14.15 mol
<u>2) Use the formula E = n × ΔH vap</u>
This is, you have to multiply the molar ΔH vaporization by the number of moles to find the total energy to boil the given amount of water.
- E = 14.15 mol × 40,650 J/mol = 575,395.5 J
<u>3) Round to the correct number of significant figures.</u>
The mass of water is the measurement with the least number of significant figures (3), so you must report the answer with 3 significant figures,