Explanation:
When there occurs sharing of electrons between two chemically combining atoms then it forms a covalent bond. Generally, a covalent bond is formed between two non-metals.
An ionic bond is defined as the bond formed due to transfer of one or more number of electrons from one atom to another. An ionic bond is always formed between a metal and a non-metal.
Every atom of an element will have orbitals in which electrons are found. These orbitals are known as energy level.
A molecule is defined as the smallest particle present in a substance or atom.
A metallic bond is formed due to mobile valence electrons shared by positive nuclei in a metallic crystal.
Thus, we can conclude that given statements are correctly matched as follows.
1). a chemical bond formed by the electrostatic attraction between ions - ionic bond
2). a chemical bond formed by two electrons that are shared between two atoms - covalent bond
3). the orbitals of an atom where electrons are found - energy level
4). the smallest particle of a covalently bonded substance - molecule
5). a bond characteristic of metals in which mobile valence electrons are shared among positive nuclei in the metallic crystal - metallic bond
C3H8+ 5 O2 --> 3 CO2 + 4 H2O
44 g. --------> 72 g
33.3 g. --------> x

Answer: The theoretical yield of H2O is 54.5
Answer:
The molar mass of the organic solid is 120.16 g/mol.
The molecular formula of an organic solid is 
Explanation:
Let the molecular mass of an organic solid be 


where,
=Elevation in boiling point = 
Mass of organic solid= 0.561 g
Mass of diphenyl = 24.9 g = 0.0249 kg (1 kg = 1000 g)
= boiling point constant = 8.00 °C/m
m = molality
Now put all the given values in this formula, we get



Percentage of carbon in an organic solid = 40.0%

x = 4.0
Percentage of hydrogen in an organic solid = 6.7%

y = 8.0
Percentage of hydrogen in an organic solid = 6.7%

y = 4.0
The molecular formula of an organic solid is 
Answer:
Metalloids, also known as semimetals are elements containing properties similar and midway between metals and nonmetals. They are found to divide the periodic table between the metals on the left and the nonmetals on the right. Metalloids often have the following properties: could be dull or shiny.