Which feature does the model show accurately?

The phase where ice changes directly to gas is called sublimation 

It will be b hydrogen

The internal energy of the system we can term it as total potential energy and kinetic energy. energy flows out of the surrounding from the system then we can say that the internal energy of the final state is lower than its initials. the sign of  δesystem is negative.δesystem = efinal - einitial=-ve  efinal  ∠einitial.

Answer : option b) two grams of hydrogen react with one gram of oxygen to form two grams of water.explanation :

the equation for synthesis of water is as follows;

here two moles of hydrogen are used with one mole of oxygen which gives one molecule of water as a product. but shana misinterpreted 2 moles as 2 grams in this equation.