The mass of
is 0.185 g.
To calculate the number of moles first calculate the molar mass of
.

Molar mass of nitrogen and oxygen is 14 g/mol and 16 g/mol respectively
Thus, 
Now, number of moles can be calculated from mass and molar mass as follows:

Therefore, number of moles of 0.185 g
is 0.0042 mol.
Answer:
Explanation:
Aluminium is used in rechargeable battery.
Aluminium ions provide the energy by flowing from anode to the cathode.
When the battery is recharged these ions comes to the anode.
The one ion gives three electrons. Which means one Al⁺³ is equal to the three Li⁺ ions. So, three unit of charge giving by ions increase the energy storage capacity.
The rechargeable batteries with aluminium gives low cost and low flammability.
It is safe to use because of inertness of aluminium and also easy to use in ambient environment.
Aluminium also have high volume capacity than lithium which means energy storage per volume is greater.
Its charge discharge cycles are also greater.
The aluminum ion batteries are also smaller in size.
Answer : The mass of the water molecule is 4.5 times greater than the mass of the helium atom.
Explanation :
Assumption : The number of water molecules is equal to the number of helium atoms
Given : The mass of water = 4.5 × The mass of helium ........(1)
The mass of Water = Mass of 1 water molecule × Number of water molecule
The mass of Helium = Mass of 1 helium atom × Number of helium atom
Now these two masses expression put in the equation (1), we get
Mass of 1 water molecule × Number of water molecule = 4.5 × Mass of 1 helium atom × Number of helium atom
As per assumption, the number of water molecules is equal to the number of helium atoms. The relation between the mass of water molecule and the mass of helium atom is,
Mass of water molecule = 4.5 × Mass of helium atom
Therefore, the mass of the water molecule is 4.5 times greater than the mass of the helium atom.
Answer:
447,25k
Explanation:
According to the ideal gas law

Where:
P: is the pressure of the gas in atmospheres.
V: is the volume of the gas in liters.
n: number of moles of the gas
R: ideal gas constant
T: absolute temperature of the gas in kelvin
now using:

Answer:
physical change because the gaseous water is chemically the same as the liquid
Explanation:
Matter can be defined as anything that has mass and occupies space. Any physical object that is found on earth is typically composed of matter. Matter are known to be made up of atoms and as a result has the property of existing in states.
Generally, matter exists in three (3) distinct or classical phases and these are; solid, liquid and gas.
A physical change can be defined as a type of change that only affects the physical form of a chemical substance (matter) without having any effect on its chemical properties. Thus, a physical change would only affect the physical appearance and properties of a chemical substance (matter) but not its chemical properties.
This ultimately implies that, a physical change result in a change of matter from one form or phase (liquid, solid or gas) to another without a corresponding change in chemical composition.
Hence, the boiling of water is considered to be a physical change because the gaseous water is chemically the same as the liquid i.e there isn't any changes in chemical composition of water when boiling.