Develop cost efficient methods to use solar energy
increase the use of wind power
reduce the use of coal and oil
Answer:
5.3 × 10⁻³ kg
Explanation:
There is some info missing. I think this is the original question.
<em>A chemist adds 135.0 mL of a 0.21 M zinc nitrate (Zn(NO₃)₂) solution to a reaction flask. Calculate the mass in kilograms of zinc nitrate the chemist has added to the flask. Be sure your answer has the correct number of significant digits.</em>
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We have 135.0 mL of a 0.21 M zinc nitrate (Zn(NO₃)₂) solution. The moles of zinc nitrate are:
0.1350 L × 0.21 mol/L = 2.8 × 10⁻² mol
The molar mass of zinc nitrate is 189.36 g/mol. The mass corresponding to 2.8 × 10⁻² moles is:
2.8 × 10⁻² mol × 189.36 g/mol = 5.3 g
1 kilogram is equal to 1000 grams. Then,
5.3 g × (1 kg/1000 g) = 5.3 × 10⁻³ kg
Answer:
The answer is True.
Explanation:
The sentence above is true it all adds up.
Well, according to the law of conservation of mass, the total mass of the reacting atoms must equal the total mass of the final rearranged products produced through the reaction. Assuming that both products are the only products produced, it would constitute the total matter produced, and since each product has a mass of 25 grams each. The total would be 50 grams. Thus the total mass of the reactants also would need to be 50 grams, as no matter is lost in a chemical reaction.