The unknown of this problem is the experimental percent of water in the compound in order to remove the water of hydrogen, given the following:
Mass of crucible, cover and contents before heating 23.54 g
Mass of empty crucible and cover 18.82 g
Mass of crucible, cover, and contents after heating to constant mass 20.94 g
In order to get the answer, determine the following:
Mass of hydrated salt used = 23.54 g – 18.82 g = 4.72 g
Mass of dehydrated salt after heating = 20.94 g – 18.82 g = 2.12 g
Mass of water liberated from salt = 4.72 g – 2.12 g = 2.60 g
Then solve the percent of water in the hydrated salt by:
% water = (mass of water / mass of hydrated salt) x 100
% water = 2.60 g / 4.72 g x 100
% water = 55.08 % in the compound
1. From grams -> mole:
=grams given x 1 mol/molar mass
So 150 g Cu x 1 mol Cu/63.546 g Cu = 2.4 mol Cu
2. From mole -> atoms
=number of mol x 6.022x10^22 atoms/1 mol
So 2.4 mol Cu x 6.022x10^22 atoms Cu/1 mol Cu = 1.4 x 10^24 atoms Cu
Answer:
44 g
Explanation:
The formula for the number of moles (n) is equal to
.
Since we need to find the mass, we derive it from the formula of the number of moles and we get that mass = n x molecular weight .
The molecular weight of
= 12 g/mol (from the carbon) + 19x4 g/mol (from the 4 fluorine atoms)= 88 g/mol
We plug in the numbers in the derived formula for the mass and we get :
mass = n x molecular weight = 0.5 mol x 88 g/mol = 44 g
In general, if a reaction is spontaneous, the reactants possess more free energy than the products.
<u>TRUE </u>
FALSE
the man made element that is in an anomalous location is Transuranium.