A 38.4−g sample of ethylene glycol, a car radiator coolant, loses 852 J of heat. What was the initial temperature of the ethylene glycol if the final temperature is 32.5°C? (c of ethylene glycol = 2.42 J/g·K)

296.33K

Explanation:

Data;

Q = 852J

mass (m) = 38.4g

θ₂ = 32.5°C = 305.5K

θ₁ = ?

c = 2.42 J/g.K

From the equation of heat transfer;

Heat transfer (Q) = MC∇θ

Q = mc(θ₂ - θ₁)

852 = 38.4 * 2.42 * ( 305.5 - θ₁ )

852 = 28389.504 - 92.928θ₁

Collect like-terms

92.928θ₁ = 27537.504

Divide both sides by 92.928 to make θ₁ the subject of formula .

θ₁ = 296.33K

20 drops hope this

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-