Answer:
45.2%
Explanation:
To calculate the percent of an element in a compound we divide the molar mass of the element by the compound and multiply that by 100
First lets find the molar mass of Fluoride
Looking at the periodic table Fluoride has a molecular mass of 18.998 g
Now we need to find the molecular mass of NaF
Looking at a periodic table, Sodium (Na) has a molecular mass of 22.990g and Fluoride has a molecular mass of 18.998 so NaF has a molecular mass of 22.990(1) + 18.998(1) = 41.988g
Now we divide the mass of fluoride by the mass of sodium fluoride and multiply that by 100 to find the percentage of fluoride that is present in NaF
Mass of Fluoride = 18.998g
Mass of Sodium Fluoride = 41.988g
Percentage of fluoride present in NaF = (18.998g / 41.988g) * 100 = 45.2%
Iron becomes rusted especially in damp air but never in a dry air, this is one of the many unique characteristics of iron. Iron is also ductile and malleable. It is found in the seventh group of the periodic table. It has four different and unique crystalline forms and completely dissolves in dilute acids. The two chemical compounds that can be found or made from iron are the bivalent iron also known as ferrous and the trivalent iron or known as ferric compounds.
Water can exist in three states.
1) Solid State: Called Ice.
2) Liquid State: Called Liquid Water.
3) Gas State: Called Steam.
Remember:
The physical states of a matter depends upon the interactions between the particles of that substance. The interactions are very strong in solid state, strong in liquid state and very weak or negligible in gas state.
If you want to change the state from solid to liquid, or from liquid to gas you will have to provide energy in order to break the interactions between the molecules. Stronger the interactions, the more is energy required to break the interactions.
Water need more energy to convert from liquid to gas phase because hydrogen bond interactions are present among the molecules of water. And the hydrogen bonds are strong enough. Hence in order to break these interactions high energy is required.
Answer:
Life science is alternatively known as biology, and physical science is subdivided into branches: physics, chemistry, astronomy and Earth science. These branches of natural science may be further divided into more specialized branches. But that is more writting to explain
Explanation: