<span>A chemist adds 155.0ml of a 4.10 X 10^-5 mmol/L of a zinc oxalate (ZnC2O4)solution to a reaction flask. Calculate the mass in micrograms of zinc oxalate the chemist has added to the flask.
1mmol = 10^-3 mol
Therefore 4.10*10^-5mmol = 4.10*10^-8mol
molar mass ZnC2O4 = 65.39+(2*12.011)+(4*15.99) = 153.372g/mol
You have 4.10*10^-8 mol/litre =153.372 * 4.10*10^-8 = 6.29*10^-6 grams / litre (* see below)
But you have 155ml. Mass of ZnC2O4 = 155/1000*6.29*10^-6 g
Mass is = 9.75*10^-7 grams
1µg = 10^-6 g
You then have 9.75*10^-7/10^-6 = 0.975µg ZnC2O4
(*see below) at this point you could have said:
1µg = 10^-6 g therefore you have a solution of 6.29µg per litre,
155ml = 6.29*155/1000 = 0.975µg ZnC2O4</span>
<u>Answer:</u>
Nitrogen gas be a mineral only, if it is in organic forms.
<u>Explanation:</u>
Most of the forms of organic nitrogen is not be taken by plants, with the exception in the form of small organic molecules. Also plants can promptly take the nitrogen when it is in other forms like ammonia and nitrate.
The microorganisms in the soil converts the organic forms of nitrogen to mineral form when they decompose organic matters and also fresh plant residues. This type of process is called mineralisation.
Um i think gold... i think?
There are 13 atoms in the product
<h3>Further explanation</h3>
Given
Reaction
H2SO4 + 2KOH --> K2SO4 + 2H2O
Required
The number of atoms
Solution
In a chemical equation, there are reactants on the left and products on the right
Reactants : H2SO4 + 2KOH
Products : K2SO4 + 2H2O
The number of atoms is determined by their reaction coefficient and the subscript of the atoms in the compound
K2SO4 (coefficient = 1) :
K = 2 atoms
S = 1 atom
O = 4 atoms
Total atoms = 7 atoms
2H2O(coefficient = 2) :
H = 2 x 2 = 4 atoms
O = 2 x 1 = 2 atoms
Total atoms = 6 atoms
Total = 13 atoms
