<h2>Answer </h2>
Option C - 320J
<u>Explanation </u>
Since ethanol solid at −120 °C and is only cooling down (it won’t change states)
. The amount of Thermodynamic properties values c is given in form of solid, liquid and gas. Amount of energy released is calculated below.
Formula,
= change in temperature x specific heat capacity for solid ethanol x 40
=> 0.5 x 16x 40 = 320J
Therefore, the 320J of heat is released when 40.0g of ethanol cools.
Answer:
1.64 moles O₂
Explanation:
Part A:
Remember 1 mole of particles = 6.02 x 10²³ particles
So, the question becomes, how many '6.02 x 10²³'s are there in 9.88 x 10²³ molecules of O₂?
This implies a division of given number of particles by 6.02 x 10²³ particles/mole.
∴moles O₂ = 9.88 x 10²³ molecules O₂ / 6.02 x 10²³ molecules O₂ · mole⁻¹ = 1.64 mole O₂
_______________
Part B needs an equation (usually a combustion of a hydrocarbon).
Answer:
[H+] = 1.74 x 10⁻⁵
Explanation:
By definition pH = -log [H+]
Therefore, given the pH, all we have to do is solve algebraically for [H+] :
[H+] = antilog ( -pH ) = 10^-4.76 = 1.74 x 10⁻⁵
Answer:
Equation 2, because K being more reactive, exchanges position with Pb in PbNO3.
Explanation: