Answer:
The heat of solution is 1.05 kJ/mol
Explanation:
NaOH → Molar mass 40 g/m
This is the mass in 1 mol
Calorimetry formula:
Q = m . c . ΔT
ΔT = T° final - T° initial = 24.5°C - 18.2°C = 6.3°C
mass = 40 g
c = 4.186 kJ/kg°C (the same as water)
So we have to convert 40 g to kg
40 g/1000 = 0.04 kg
Q = 0.04 kg . 4.186 kJ/kg°C . 6.3 °C = 1.05 kJ
It stays the same, because the concentration of H+ ions doesn't change.
Answer:Osmotic pressure is the minimum amount of pressure a solution must exert in order to prevent from crossing a barrier by osmosis. Solute molecules have difficulty crossing semipermeable membranes, so the more solutes that are in a solution, the higher the osmotic pressure will be. Between 30% sucrose and 60% sucrose, 60% sucrose will have a greater osmotic pressure than 30% because it has a higher percentage of solutes. However, since sucrose has a higher potential to cross semipermeable membranes and is more absorbable than magnesium sulfate, magnesium sulfate would have a higher osmotic pressure than 60% sucrose even though 60% sucrose has higher molecules.
Explanation:
Answer is: Ka for propanoic acid is 6,57·10⁻⁵.
Chemical reaction: C₂H₅COOH(aq) + H₂O(l) ⇄ C₂H₅COO⁻(aq) + H₃O⁺(aq).
n(C₂H₅COOH) = 0,04 mol.
V(C₂H₅COOH) = 750 mL = 0,75 L.
c(C₂H₅COOH) = 0,04 mol ÷ 0,75 L.
c(C₂H₅COOH) = 0,053 mol/L = 0,053 M.
[C₂H₅COO⁻] = [H₃O⁺] = 1,84·10⁻³ M = 0,00184 M.<span>
[HCN] = 0,053 M - 0,00184 M = 0,0515 M.
Ka = [</span>C₂H₅COO⁻] ·
[H₃O⁺] / [C₂H₅COOH].
Ka = (0,00184 M)² / 0,0515 M.
Ka = 6,57·10⁻⁵.
Answer:
A; 
Explanation:
The best way to start solving this problem is to start with the molecule with the most atoms. Since there are 12 carbons on the left, you need 12 on the right so 12 would need to be placed in front of carbon dioxide. Also you need 22 hydrogens and in each molecule of water, there are two hydrogen molecules so you need 11 molecules of water. After balancing you find that you need 24 oxygen on the left so you place the coeffecient 12 in front of the oxygen molecule.
