What is the specific heat of an unknown substance if a 2.50 g sample releases 12 calories as its temperature changes from 25°c to 20°c?
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oc
od
-0.96 cal/g °c
1,350 cal/g °c
0.96 cal/g °c
30 cal/g °c

The atoms in a nickel crystal vibrate as harmonic oscillators with an angular frequency of 2.3 × 1013 rad/s. the mass of a nickel atom is 9.75 × 10-26 kg. what is the difference in energy between adjacent vibrational energy levels of nickel? (h = 6.626 × 10-34 j • s, , 1 ev = 1.60 × 10-19 j)