What are the signs of δs univ, δs surr, and δs sys, respectively, for water freezing at −10°c?

Explanation:

δs sys = change in entropy of the system

= dQ / T

dQ is heat exchanged . It is negative as heat is given out and T = 273 k  so

δs sys = - dQ / T

Its sign will be negative.

δs surr = dQ / T₁ , dQ is heat given by the water to freeze . It is positive

δs surr = + dQ / T₁ , T₁ is temperature of the surrounding

Sign of δs surr is positive .

δs univ = δs sys + δs surr

- dQ / T + dQ / T₁

T < T₁

dQ / T >dQ / T₁

- dQ / T + dQ / T₁ will be negative

δs univ will be negative .