A 5.000 gram sample of hydrated nickel (II) cyanide, Ni(CN)2·xH2O is heated according to the procedure described in this laboratory. After heating, the sample is found to weigh 3.029 grams. How many moles of H2O were present in the sample? How many moles of Ni(CN)2 were present?
Due to heating the water of crystallisation is lost .
Loss of water = (5.000 - 3.029) = 1.971 g.
Moles of water present = (1.971/18)
= 0.1095.
Mass of Ni(CN)2 = 3.029 grams
Molar mass of Ni(CN)2 = 110.73 g/mol.
Then moles of Ni(CN)2 = ( 3.029/110.73) = 0.0273
Now,
Ni(CN)2 : H2O
= 0.0273 : 0.1095
1:4
Hence, formula is Ni(CN)2, 4 H2O.
A 5.000 gram sample of hydrated nickel (II) cyanide, Ni(CN)2·xH2O is heated according to the procedure...
1. A 5.000 gram sample of hydrated nickel (II) cyanide, Ni(CN)2·xH2O is heated according to the procedure described in this laboratory. After heating, the sample is found to weigh 3.029 grams. How many moles of H2O were present in the sample? How many moles of Ni(CN)2 were present? 2. Determine the empirical formula of the hydrated salt from question 1. Write your answer in the format, Ni(CN)2∙ x H2O, where “x” is an integer.
A 6.2351 g sample of an unknown hydrate of cobalt(II) bromide is heated until all the water of hydration is removed. The CoBr2 that remains has a mass of 5.0000 g. 1. How many moles of CoBr2 are in the sample? mol 2. How many grams of water were lost in the dehydration? g 3. How many moles of water were lost? (mol) 4. What is the value of "n" in the formula CoBr2 · n H2O? (1, 2, 3,...
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1. After a 6.387 g sample of impure SnCl4.2H2O
(Mn=296.7 g/mol) was throughly heated, 5.690 g remained
b) How many grams of the hydrate were present in the
sample?
c) What is the % m/m of the hydrate in the sample?
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