None a lot of hand or sum
A protective layer composed of overlapping cells, like fish scales or roof tiles, but facing downwards. The outer cuticle holds your hair in your hair follicle by means of a Velcro-like bond. It also minimizes the movement of water (moisture) in and out of the underlying cortex.
Answer:
PV=nRt
Therefore n(number of moles)=PV/RT
=>(0.49×3.80)/(0.08206×320)
Therefore Number of moles is = 0.071mols
Explanation: By using the Real gas equation..
PV=NRT .
We can solve for the number of moles of Ar by making N the subject..
Always make sure you pressure is In atm, your Volume is in Litres and temperature in degree Kelvin.
Also Recall the universal gas constant R used in this type of questions which is 0.08206.
Hence l, by making N the subject we get our answer as
Answer:
carbon dioxide is acidic and when it comes in contact with blue litmus paper it turns red
Explanation:
Answer:
2.04 x 10²⁴ molecules
Explanation:
Given parameters:
Mass of Be(OH)₂ = 145.5g
To calculate the number of molecules in this mass of Be(OH)₂ we follow the following steps:
>> Calculate the number of moles first using the formula below:
Number of moles = mass/molarmass
Since we have been given the mass, let us derive the molar mass of Be(OH)₂
Atomic mass of Be = 9g
O = 16g
H = 1g
Molar Mass = 9 + 2(16 + 1)
= 9 + 34
= 43g/mol
Number of moles = 145.5/43 = 3.38mol
>>> We know that a mole is the amount of substance that contains Avogadro’s number of particles. The particles can be atoms, molecules, particles etc. Therefore we use the expression below to determine the number of molecules in 3.38mol of Be(OH)₂:
Number of
molecules= number of moles x 6.02 x 10²³
Number of molecules= 3.38 x 6.02 x 10²³
= 20.37 x 10²³ molecules
= 2.04 x 10²⁴ molecules
