A combustion involves a chemical reaction.
Energy needed : Q = 1105.5 J
<h3>Further explanation</h3>
Given
mass = 55 g
Temperature from -10°C to 0°C
Required
Energy
Solution
Heat can be calculated using the formula:
Q = mc∆T
Q = heat, J
m = mass, g
c = specific heat, joules / g ° C
∆T = temperature difference, ° C / K
Input the value :
Q = 55 g x 2.01 J/g ° C x (0-(-10))
Q = 1105.5 J
The answer is cold water because the water is cold and it’s not using thermal energy
Answer is: pH of a buffer is 4.64.
ck(CH₃COOH) = 0.45 M.
cs(CH₃COONa) = 0.35 M.
Ka = 1.8·10⁻⁵.
<span>pKa = -logKa.
</span>pKa = -log(1.8·10⁻⁵) = 4.75.
<span>Henderson–Hasselbalch equation: pH = pKa + log(cs/ck).
</span>pH = 4.75 + log(0.35M/0.45M).
pH = 4.75 - 0.11.
pH = 4.64.
pH (potential of hydrogen) is a numeric
scale used to specify the acidity or basicity an aqueous solution.