Technology of course and Pliers make work easier by holding parts. By gripping small things in awkward locations.
Answer:
ΔH = 1270kJ
Explanation:
Let's consider the following thermochemical equation.
B(s) + 3/2 O₂(g) → B₂O₃(s), ΔH = −1270kJ
Since ΔH < 0, this reaction is exothermic. According to the Lavoisier-Laplace law, if we reverse a reaction, its enthalpy will have the same value and opposite sign than the direct reaction.
B₂O₃(s) → B(s) + 3/2 O₂(g), ΔH = 1270kJ
For the inverse reaction, ΔH > 0, which means that it is endothermic.
Answer:
A. Yes, Amanda find the number of moles of NaCl correctly.
B. 0.73 M.
Explanation:
<em>A. Did Amanda find the number of moles of NaCl correctly? If not, explain.
</em>
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Yes, Amanda find the number of moles of NaCl correctly.
- The relation to find the no. of moles of NaCl is:
<em>No. of moles (n) of NaCl = mass/molar mass.</em>
mass of NaCl = 32.0 g, molar mass of NaCl = 58.45 g/mol.
∴ No. of moles (n) of NaCl = mass/molar mass = (32.0 g)/(58.45 g/mol) = (32.0 g NaCl)*(1 mol of NaCl)/(58.45 g NaCl) = 0.547 mol ≅ 0.55 mol.
<em>B. What does Amanda need to do next to calculate the molarity of the NaCl solution? Show your work for full credit.</em>
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- Molarity is the no. of moles of solute dissolved in a 1.0 liter of a solution.
∴ M = (no. of moles of NaCl)/(volume of solution (L)) = (0.55 mol)/(0.75 L) = 0.73 M.
I think the answer is C , more dense
