Answer:
A. When two aqueous solutions are mixed, a precipitate is formed.
Explanation:
The precipitate (a solid substance that falls from the liquid) is the result of a chemical reaction taking place between the liquids.
The other three answer choices are indicative of physical changes (temperature change, phase change, color change).
A general equation for a combustion reaction would be expressed as follows:
CxHy + (x+y/2)O2 = xCO2 + y/2H2O
Propane would obviously would only have carbon and hydrogen in its structure. Assuming a complete combustion, all of the carbon atoms would go to carbon dioxide and all of the hydrogen atoms to water. To determine the empirical, we determine the number of carbon and hydrogen atoms present.
moles C = 2.461 g CO2 ( 1 mol / 44.01 g ) ( 1 mol C / 1 mol CO2 ) = 0.06 mol C
moles H = 1.442 g H2O ( 1 mol / 18.02 g ) ( 2 mol H / 1 mol H ) = 0.16 mol H
Then, we divide the smallest amount to the each mole of the atoms. We do as follows:
C = 0.06 / 0.06 = 1
H = 0.16 / 0.06 = 2.67
Then we multiply a number in order to obtain a whole number ratio between the atoms.
1 CH2.67
2 C2H5.34
3 C3H8 <-------- empirical formula
When solutions of sodium sulfide and copper(ii) sulfate are mixed, a precipitate of copper(ii) sulfide is formed. The net ionic equation for this reaction is Cu⁺² (aq) + S⁻² (aq) → CuS (s).
<h3>What is Balanced Chemical Equation ?</h3>
The balanced chemical equation is the equation in which the number of atoms on the reactant side is equal to the number of atoms on the product side in an equation.
Now first write the balanced chemical equation
CuSO₄ (aq) + Na₂S (aq) → CuS(s) + Na₂SO₄ (aq)
Now write the net ionic equation
Cu⁺² (aq) + SO₄⁻² (aq) + 2Na⁺ (aq) + S⁻² (aq) → CuS (s) + 2Na⁺ + SO₄⁻² (aq)
So the net ionic equation is
Cu⁺² (aq) + S⁻² (aq) → CuS (s)
Thus from the above conclusion we can say that When solutions of sodium sulfide and copper(ii) sulfate are mixed, a precipitate of copper(ii) sulfide is formed. The net ionic equation for this reaction is Cu⁺² (aq) + S⁻² (aq) → CuS (s).
Learn more about the Balanced Chemical Equation here: brainly.com/question/26694427
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