The model of the atom has dramatically changed over many many years.We learned atoms make up different substances and are the smallest particles of matter, which have subatomic particles that are very small portions of matter. At first scientist only thought there were electrons which are negatively charged.
Answer: Formal Charges: Hydrogen = 0 and Oxygen = +1
Unshared Pair of electrons: Hydrogen = 0 and Oxygen = 2
Explanation:
The attachment below shows the Lewis structure and the calculations
Since Group 2 alkali earth metals have 2 valence electrons, they tend to lose those 2 when forming ionic bonds. And the Loss of Electrons = Oxidation (L.E.O. for short). Therefore this group, including Mg and Ca, have an oxidation of [+2].
So the correct answer is C) +2
.
Oxygen-16 is the atom in question.
- Atomic number: 8.
- Mass number: 16.
<h3>Explanation</h3>
The superscript of the ion says "2-". That means that the ion here carries a charge of -2.
- The charge is negative, meaning that there are more electrons (which are negative) than protons (which are positive) in that ion.
- The size of the charge is 2. There are two more electrons than protons in that ion.
There are 10 electrons in total in that ion. There are two more electrons than protons. That means that there are 10 - 2 = 8 protons in that ion.
The atomic number of an atom is the same as its number of protons. The atomic number of X is 8.
The atomic number determines the element. Atomic number 8 is oxygen. Thus element X is oxygen.
Mass number is the sum of number of protons and neutrons in an atom. 8 + 8 = 16 for this atom.
Answer: The capillary rise(h) in the glass tube is = 0.009m
Explanation:
Using the equation
h = 2Tcosθ/rpg
Given
Contact angle, θ = Zero
h = height of the glass tube=?
T = surface tension = 
r = radius of the tube = 0.1mm =0.0001m
p= density of ethanol = 
g= 
h = 
h= 0.09m
Therefore the capillary rise in the tube is 0.09m