Answer:
Heat energy required (Q) = 10.736 KJ
Explanation:
Given:
Specific heat of ethanol (C) = 2.44 J/g °C
Mass of ethanol (M) = 50 gram
Initial temperature (T1) = -20°C
Final temperature (T1) = 68°C
Find:
Heat energy required (Q) = ?
Computation:
Change in temperature (ΔT) = 68°C - (-20°C)
Change in temperature (ΔT) = 88°C
Heat energy required (Q) = mC(ΔT)
Heat energy required (Q) = (50)(2.44)(88)
Heat energy required (Q) = 10,736 J
Heat energy required (Q) = 10.736 KJ
This problem could be solved easily using the Henderson-Hasselbach equation used for preparing buffer solutions. The equation is written below:
pH = pKa + log[(salt/acid]
Where salt represents the molarity of salt (sodium lactate), while acid is the molarity of acid (lactic acid).
Moles of salt = 1 mol/L * 25 mL * 1 L/1000 mL = 0.025 moles salt
Moles of acid = 1 mol/L* 60 mL * 1 L/1000 mL = 0.06 moles acid
Total Volume = (25 mL + 60 mL)*(1 L/1000 mL) = 0.085 L
Molarity of salt = 0.025 mol/0.085 L = 0.29412 M
Molarity of acid = 0.06 mol/0.085 L = 0.70588 M
Thus,
pH = 3.86 + log(0.29412/0.70588)
pH = 3.48
you’re made partly of carbon so is clothes, furniture, plastics, yr household machines
Answer:
B
Explanation:
<em>Both plain and plateau have flat surfaces. However, a plain is located in a low-lying area while a plateau is located on an elevated area. In essence, a plateau can be viewed as an elevated plain or a plain that is bordered by cliffs.</em>
The correct option is B.
Answer:
Barium
Explanation:
-Atomic #56
-5th element inn group 2
- soft
- silvery alkaline earth metal