Answer:
The range of atoms = (30-300 pm) depending upon the element
Explanation:
The Atomic radii of the atom is the distance from the center of the circle to the outermost orbital.
The center of the circle is the nucleus and the radii is the outermost boundary.
The actual size of the atom is decided on the basis of the Zeff . Also known as <em>effective nuclear charge.</em>
<em>Zeff: It is the net positive charge felt by the outermost electron by the nucleus.</em>
<em>The value of Zeff depends upon the shielding constant. More the shielding less will be the Zeff . Hence the size of the atom increases.</em>
Due to shielding the outermost electrons feel less pull of nucleus.
<em>The greater the Zeff , the smaller the radius of the atom.</em>
The formula used to calculate the atomic mass is :
pm
Here "pm"= picometers
<u>The size of the smallest atom H-atom = 120 pm</u>
<u>The range of atoms = (30-300 pm)</u>
Answer:
Look at the properties of Oxygen and Silicon - the two most abundant elements in the Earth's crust - by clicking on their symbols on the Periodic Table.
Explanation:
Answer:
D
Explanation:
There are principally three states of matter. These are the solid, liquid and gaseous states. The gaseous state has the highest degree of disorderliness as gas particles can move randomly while the solid state has the highest level of compactness.
Hence, we need to be adequately fed with information as regards the phase change to know if entropy has decreased or increased.
A. is wrong
Evaporation is a change of state to the gaseous state meaning there is an increased entropy.
B. is wrong
Sublimation is a change of state which means a solid substance like iodine or naphthalene changes its state directly to the gaseous state. There is an increased entropy here too.
C is wrong
Melting of ice means going from ice block to liquid water. This is synonymous to going from the solid state to the liquid state which is an increased entropy
D is correct
Condensation involves going from the gaseous state to the liquid state. This means going from a less ordered state to a more ordered state. This is accompanied by an entropy decrease.
E is wrong
While there are some processes that increase entropy, we also have some process that decrease entropy.
I think Both protons and neutrons (and their anti-particles) froze out at 1013 K, about 0.0001 seconds after the Big Bang. Protons and neutrons are sub atomic particles of an atom that are found in the nucleus of an atom. Proton is the positively charge particle while the neutron has no charge. The proton positive charge accounts for the positive nuclear charge.
Explanation:
The number of protons in an atom is the atomic number.
Mass number is the number of protons plus neutrons in an atom.
Mass number = number of protons + number of neutrons
Atomic number = number of protons
Atomic number gives the symbol of the element
Number Number Atomic Mass Symbol
Protons neutrons Number Number
A 7 B 15 C
D E 26 56 F
A, number of protons = B
Mass number = protons + neutrons
15 = protons + 7
Protons = 15 - 7 = 8
Atomic number 8 is for oxygen = C
Atomic number = number of protons = D = 26
Number of neutrons ;
E = Neutrons = mass number - protons = 56 - 26 = 30
Atomic number 26 is for Iron = F
