Which of the following processes have a δs > 0? a. n2(g) + 3 h2(g) → 2 nh3(g) b. na2co3(s) + h2o(g) + co2(g) → 2 nahco3(s) c. ch3oh(l) → ch3oh(s) d. all of these processes have a δs > 0. e. ch4(g) + h2o (g) → co(g) + 3 h2(g)

ΔS > 0 only for choice E: CH4(g) + H2O (g) → CO(g) + 3 H2(g)

Explanation:

Our strategy in this question is to use the trend in entropies :

S (solids)  less than S (liquids) less than S (gases)

Also we have to look for the  molar quanties involved of each state and their change to answer the question:

A. N2(g) + 3 H2(g) → 2 NH3(g)

Here we have 4 moles gases going to 2 moles of products, so the change in entropy is negative.

B. Na2CO3(s) + H2O(g) + CO2(g) → 2 NaHCO3(s)

The change in entropy is negative since we have 2 mol gases in the reactants and zero in the products.

C. CH3OH(l) → CH3OH(s)

A liquid has a higher entropy than a solid so ΔS is negative

D. False see A,B,C

E. The change in moles of gases is 4 - 2= 2, therefore  ΔS is greater than O.

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.