# chem, predicting direction of change in entropy

Predict the direction of the entropy in each reaction.
a. CaCO3(s)-> CaO(s) +CO2(g0
b. NH3(g)+HCl(g)->NH4Cl(s)
c. 2NaHCO3-> Na2CO3(s)+H20(g) +CO2
d. CaO(s)+CO2(g)-> CaCO3

1. 👍
2. 👎
3. 👁
1. The secret here is to visualize the randomness of the substances. Entropy increases as we go from solid to liquid to gas. Solids are orderly with atoms essentially locked into place, liquids less orderly and more degrees of freedom for the molecules, gases the molecules can go every which way.
a. CaCO3 is solid, CaO is solid BUT CO2 is a gas so entropy increases in going from left to right.
b. gases going to solid; entropy decreases from left to right.

1. 👍
2. 👎
2. Positive

1. 👍
2. 👎

## Similar Questions

1. ### chemistry

Calculate Delta G for each reaction using Delta Gf values: answer kJ ...thank you a) H2(g)+I2(s)--->2HI(g) b) MnO2(s)+2CO(g)--->Mn(s)+2CO2(g) c) NH4Cl(s)--->NH3(g)+HCl(g) is this correct? a) H2(g)+I2(s)--->2HI(g) From tables: G HI

2. ### Chemistry

Consider the following reaction: CaCO3(s)→CaO(s)+CO2(g). Estimate ΔG∘ for this reaction at each of the following temperatures. (Assume that ΔH∘ and ΔS∘ do not change too much within the given temperature range.) for

3. ### Chemistry

A 10.0-g sample of solid NH4Cl is heated in a 5.00-L container to 900.°C. At equilibrium the pressure of NH3(g) is 1.51 atm. NH4Cl(s) mc011-1.jpg NH3(g) + HCl(g) The equilibrium constant, Kp, for the reaction is:

4. ### Chemistry

100 mL of each of the following solutions is mixed; which one of the mixed solutions is a buffer? A) 1.0 M NH3(aq) + 0.6 M KOH(aq) B) 1.0 M NH4Cl(aq) + 1.0 M KOH(aq) C) 1.0 M NH3(aq) + 0.4 M HCl(aq) D) 1.0 M NH4Cl(aq) + 0.4 M

1. ### AP Chem

Reaction 1: NaOH + HCL --> H20 + NaCl delta H of -100.332 kj/mol Reaction 2: NaOH + NH4Cl --> NH3 + H20 : delta H of 358.639 kj/mol Reaction 3: HCl + NH3 --> NH4Cl : delta H of -51.701 kj/mol Use your answers from question 2 above

2. ### Chemistry

For the reaction below, Kp = 1.16 at 800.°C. CaCO3(s) CaO(s) + CO2(g) If a 25.0-g sample of CaCO3 is put into a 10.2-L container and heated to 800.°C, what percent of the CaCO3 will react to reach equilibrium?

3. ### chemistry 101

Consider the following reaction. CaO (s) + CO2 (g) = CaCO3 (s) A chemist allows 14.4 g of CaO and 13.8 g of CO2 to react. When the reaction is finished, the chemist collects 19.4 g of CaCO3. Determine the limiting reactant,

1. Which is true about spontaneous reactions? a. For a reaction to be spontaneous, Keq = 1. b. Spontaneous reactions happen very rapidly. c. A chemical reaction is spontaneous in both directions. *** d. Spontaneous reactions do

1. ### Chemistry

The reaction of hydrochloric acid (HCl) with ammonia (NH3) is described by the equation: HCl + NH3 → NH4Cl A student is titrating 50 mL of 0.32 M NH3 with 0.5 M HCl. How much hydrochloric acid must be added to react completely

2. ### Chemistry

Calculate the enthalpy change (ΔH) for: HCl(aq) + NH3(aq) → NH4Cl(aq) The reaction of 50.0 mL of 1.00 M HCl with 50.0 mL of 1.00 M NH3 causes a temperature rise of 6.4 ˚C in the resulting 100.0 mL of solution. The NH4Cl

3. ### chemistry

Calcium carbonate CaCO3 reacts with stomach acid (HCl, hydrochloric acid) according to the following equation: CaCO3(s)+2HCl(aq)->CaCl2(aq)+H2O(l)+CO2(g) Tums, an antacid, contains CaCO3. If Tums is added to 35.0 mL of 0.300 M

4. ### Chemistry

Consider the following equilibrium: NH4Cl(s)--->NH3(g) + HCl(g) Suppose a vessel containing NH4Cl(s), NH3(g) and HCl(g) is at equilibrium. If the volume of vessel is instantaneously doubled while keeping the temp constant when a