<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>
Answer:
25%
Explanation:
Ammonium Chloride NH4CI Fertilizer-grade NH4Cl usually contains 25% N. About two-thirds of the world capacity for manufacture of this material is located in Japan, with the remaining one-third situated in India and China.
Answer:
There are 79 protons in the nucleus of one Gold atom.
Explanation:
The number of protons of any given atom/element can be determined by the atomic number of the specific element, which is found on the periodic table.
Answer:
37.1 calories.
Approximately, 37.1 = 40 calories.
Explanation:
So, without mincing words let's dive straight into the solution to the question above.
We are given the following parameters which are going to help in solving this particular Question.
The mass of broccoli = 86g of broccoli, mass of carbohydrates present = 6g of carbohydrates, the mass of protein present = 2.6g of protein and the mass of fat present = 0.3g of fat.
Therefore, the nutritional energy content (in Calories) = (6 × 4) + (2.6 × 4) + (0.3 × 9) = 10.4 + 24 + 2.7 = 37.1
Hence, the nutritional energy content (in Calories) = 37.1 calories.
Approximately, 37.1 = 40 calories.
Answer:
Explanation:
Strontium chlorate appears as a moist solid or semi-solid slurry of white crystals. May explode under exposure to heat or fire. Used in pyrotechnics
strontium chlorate | Sr(ClO3)2 - PubChem.
Description: Strontium chlorate appears as a ...
Synonyms: STRONTIUM CHLORATE7791-10-...
Molecular Formula: Sr(ClO3)2 or Cl2O6Sr