A Chemical change is any form of chemical reaction changing the state of the matter involved. When you fry an egg, you are making a reaction between the heat and the chemicals that make up the egg. Therefore once you have fried that egg, you have completed a chemical reaction. This is why it's a chemical change when you fry an egg.
The actual number of atoms of each element present in the molecule of the compound is represented by the formula known as molecular formula.
Molar mass of the unknown compound = 223.94 g/mol (given)
Mass of each element present in the unknown compound is determined as:
- Mass of carbon, :
- Mass of hydrogen, :
- Mass of chlorine, :
Now, the number of each element in the unknown compound is determined by the formula:
- Number of moles of :
- Number of moles of :
- Number of moles of
Dividing each mole with the smallest number of mole, to determine the empirical formula:
Multiplying with 2 to convert the numbers in formula into a whole number:
So, the empirical formula is .
Empirical mass =
In order to determine the molecular formula:
n =
n =
So, the molecular formula is:
Answer:
1.B
2.A
3. B
Explanation:
1. A chemical bond is the physical phenomenon of chemical substances being held together by attraction of atoms to each other through sharing
2. so 2 is electrons of one atom are transferred permanently to another atom.meaning the answer is A
3. is When atoms combine by forming covalent bonds, the resulting collection of atoms is called a molecule. We can therefore say that a molecule is the simplest unit of a covalent compound.
Answer:
(a)
(b)
(c)
(d)
(e)
Explanation:
To calculate de pH of an acid solution the formula is:
were [H^{+}] is the concentration of protons of the solution. Therefore it is necessary to know the concentration of the protons for every solution in order to solve the problem.
(a) and (c) are strong acids so they dissociate completely in aqueous solution. Thus, the concentration of the acid is the same as the protons.
(b) and (e) are strong bases so they dissociate completely in aqueous solution too. Thus, the concentration of the base is the same as the oxydriles. But in this case it is necessary to consider the water autoionization to calculate the protons concentration:
clearing the
(d) is a weak base so it is necessary to solve the equilibrium first, knowing
The reaction is → so the equilibrium is
clearing the <em>x</em>
Answer: -
After rain fall occurs, water accumulates
.
This water is called ground water. This water slowly flows under the ground through the pore spaces in the soil. The water continues to go under the soil till it reaches a certain point where it can no longer go down.
In this region the water slowly accumulates forming a water reservoir called aquifer. The aquifer is a place under the soil which is saturated with water. The upper surface of this zone of saturation is called the water table.