Question 3 (1 pts) 2 As (s) + 6 NaOH (aq) → 2 Na3AsO3 (s) + 3 H2 (g)

If 34.0g of As react with excess NaOH at STP, what volume of H2 will be produced in liters?

Question 4 (1 pts)
SnO2 (s) + 2 H2 (g) → Sn (s) + 2 H2O (l)

What mass of water is produce when 79.0g of SnO2 are consumed in the reaction above?

Question 5 (1 pts)
C3H8(g) + 5 O2 (g) → 3 CO2 (g)+ 4 H2O (g)

What volume of oxygen is required to completely combust 0.499L of propane (C3H8) at STP?

i had this on my unit activity, i can you if you are a plato student. are you a plato student?

the volume increases

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.