Answer:
28.7%
Explanation:
First let us write the formula of manganese (ii) nitrate tetrahydrate. This is shown below:
Mn(NO3)2.4H2O
The molar mass of Mn(NO3)2.4H2O = 55 + 2[14 + (3x16)] + 4[(2x1) + 16]
= 55 + 2[14 + 48] + 4[2 + 16]
= 55 + 2[62] + 4[18]
= 55 + 124 + 72
= 251g/mol
Mass of water of crystallization in Mn(NO3)2.4H2O = 4H2O
= 4[(2x1) + 16]
= 4[2 + 16]
= 4[18]
= 72g
The percentage by mass of water of crystallization in manganese (ii) nitrate tetrahydrate Mn(NO3)2.4H2O, is given by:
Percentage of water of crystallization = Mass of water of crystallization / Molar Mass of Mn(NO3)2.4H2O x 100
= 72/251 x 100
= 28.7%
Therefore the percentage of water of crystallization in manganese (ii) nitrate tetrahydrate is 28.7%
