Answer:
All description is given in explanation.
Explanation:
Van der Waals forces:
It is the general term used to describe the attraction or repulsion between the molecules. Vander waals force consist of two types of forces:
1. London dispersion forces
2. Dipole-dipole forces
1. London dispersion forces:
These are the weakest intermolecular forces. These are the temporary because when the electrons of atoms come close together they create temporary dipole, one end of an atom where the electronic density is high is create negative pole while the other becomes positive . These forces are also called induce dipole- induce dipole interaction.
2. Dipole-dipole forces:
These are attractive forces , present between the molecules that are permanently polar. They are present between the positive end of one polar molecules and the negative end of the other polar molecule.
Hydrogen bonding:
It is the electrostatic attraction present between the atoms which are chemically bonded. The one atom is hydrogen while the other electronegative atoms are oxygen, nitrogen or flourine. This is weaker than covalent and ionic bond.
Ionic bond or electrostatic attraction:
It is the electrostatic attraction present between the oppositely charged ions. This is formed when an atom loses its electron and create positive charge and other atom accept its electron and create negative charge.
Hydrophobic interaction:
It is the interaction between the water and hydrophobic material. The hydrophobic materials are long chain carbon containing compound. These or insoluble in water.
Covalent bond:
These compounds are formed by the sharing of electrons between the atoms of same elements are between the different element's atoms. The covalent bond is less stronger than ionic bond so require less energy to break as compared to the energy require to break the ionic bond.
Answer:
4) transferred from the valence shell of one atom to the valence shell of another atom
Explanation:
Electrons are located outside of the nucleus which contains the protons and the neutrons.
For bonds to form, valence electrons located in the outermost shell electrons are involved. These are the valence electrons. These outer shell electrons can be shared or transferred between two combining atoms to form stable atoms.
In ionic bonds, the electrons are transferred from one specie to another. The atom that loses the electrons becomes positively charged and the receiving atom becomes negatively charged. This is the crux of ionic bonds.
Silicon is the element having a mass of 28.09 g
<u>Explanation</u>:
- Silicon is the element having an atomic mass of 28.09 g / mol. So 28.09 g of silicon contains 6.023
10^23 atoms. One mole of each element can produce one mole of compound.
- The Atomic weight of an element can be determined by the number of protons and neutrons present in one atom of that element. So atomic weight expressed in grams always contain the same number of atoms( 6.023 10^23).
- Avagadro number is the number of atoms of 1 mole of any gas at standard temperature and pressure. It has been determined that 6.023 10^23 atoms of an element are equal to the average atomic mass of that element.
The number of molecules : 4.967 x 10²⁴
<h3>Further explanation
</h3>
A mole is a number of particles(atoms, molecules, ions) in a substance
This refers to the atomic total of the 12 gr C-12 which is equal to 6.02.10²³, so 1 mole = 6.02.10²³ particles
Can be formulated :
N = n x No
N = number of particles
n = mol
No = 6.02.10²³ = Avogadro's number
8.25 moles of C₈H₁₈
The number of molecules :
Answer:
A device that does work with only one movement and changes the size or direction of a force is a simple machine.
Explanation:
- For applying force, any used basic mechanical devices are simple machines.
- Simple machine changes the direction as well as the amplitude of the applied force i.e. we can increase or decrease the magnitude of the force.
- A simple machine is the most basic mechanism to use the force as we need in big mechanical machines.
- Some of the examples of simple machines are inclined plane, lever, wedge, wheel and axle, pulley, and screw.
