C. The thermometer reads 100
1 CH4 (g) + 2 O2 (g) -----> CO2 (g) + 2H2O(l) ΔH= - 890 kJ
1 mol 2 mol
1) If ΔH has minus, it means "release". We need only "release" choices.<span>
2) From reaction
1 mol </span>CH4 (g) "releases" ΔH= - 890 kJ - We do not have this choice.
2 mol O2 (g) "release" ΔH= - 890 kJ, so
1 mol O2 (g) "release" ΔH= - 445 kJ
Correct answer is B.
The reaction is an equilibrium represented by the equation
<span>Ag2CO3(s) + 2 HNO3(aq) <----> 2 AgNO3(aq) + H2O(l) + CO2(g) </span>
From the <span>Le Chatelier's Principle which </span>states that changing a factor such as concentration, temperature, or pressure of a reaction at equilibrium will cause the reaction to shift in the direction that counteracts the effect of that change.
Therefore; the CO2 produced starts escaping and the concentration and pressure of CO2 drops. The system responds by trying to increase the concentration and pressure of CO2 by producing more. This means more and more Ag2CO3 will dissolve due to reaction with the acid, HNO3.
This continues until one of the reactants is exhausted.
I believe the answer is Limestone
Limestone is one of the vital minerals that is used to make cement. It is a sedimentary rock composed mostly of the calcium carbonate and, according to mineral coalition, it comprises about 15% of the Earth's sedimentary crust.
