<h3>
Answer:</h3>
8.64 g
<h3>
Explanation:</h3>
- Density is the ratio of mass of substance to its volume.
- It is calculated by dividing the mass of a substance by its volume.
- Density = Mass ÷ Volume
In this case we are given,
Volume of sodium chloride = 4.00 cm³
Density of sodium chloride = 2.16 g/cm³
We are required to calculate the mass of sodium chloride,
Rearranging the formula;
Mass = Density × volume
Mass of sodium chloride = 2.16 g/cm³ × 4.00 cm³
= 8.64 g
Therefore, the mass of sodium chloride is 8.64 g
Answer:
ΔH = -20kJ
Explanation:
The enthalpy of formation of a compound is defined as the change of enthalpy during the formation of 1 mole of the substance from its constituent elements. For H₂S(g) the reaction that describes this process is:
H₂(g) + S(g) → H₂S(g)
Using Hess's law, it is possible to sum the enthalpies of several reactions to obtain the change in enthalpy of a particular reaction thus:
<em>(1) </em>H₂S(g) + ³/₂O₂(g) → SO₂(g) + H₂O(g) ΔH = -519 kJ
<em>(2) </em>H₂(g) + ¹/₂O₂(g) → H₂O(g) ΔH = -242 kJ
<em>(3) </em>S(g) + O₂(g) → SO₂(g) ΔH = -297 kJ
The sum of -(1) + (2) + (3) gives:
<em>-(1) </em>SO₂(g) + H₂O(g) → H₂S(g) + ³/₂O₂(g) ΔH = +519 kJ
<em>(2) </em>H₂(g) + ¹/₂O₂(g) → H₂O(g) ΔH = -242 kJ
<em>(3) </em>S(g) + O₂(g) → SO₂(g) ΔH = -297 kJ
<em>-(1) + (2) + (3): </em><em>H₂(g) + S(g) → H₂S(g) </em>
<em>ΔH =</em> +519kJ - 242kJ - 297kJ = <em>-20 kJ</em>
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I hope it helps!
#6 should be the independent variable because that's the one you can control
A conjugate acid is a conjugate base with hydrogen ions attached to it. In this case, the conjugate base is the carbonate ion, CO₃⁻². This ion can have two hydrogen ions, so the conjugate acid is:
H₂CO₃
This compound is known as carbonic acid.
The weight/weight percent(%w/w) of NaCl in solution : 33.03%
<h3>Further explanation</h3>
Given
Mole fraction of NaCl : 0.132
Required
The weight/weight percent of NaCl
Solution
1 mol solution : 0.132 mol NaCl + 0.868 mol H₂O
mass NaCl :
mass H₂O :
Total mass = 7.714 + 15.64 = 23.354 g
