# college

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Calculate the heat of formation of water from its constituent elements from the following information:

3 H2 (g) + O3 (g) → 3H2O ∆H = ?
2 H2 (g) + O2 (g) → 2H2O ∆H = - 483.6
3 O2 (g) → 2O3 (g) ∆H = 284.5

You are given 2.0 grams of zinc and 2.5 grams of silver nitrate and are told they react in the following manner: Zn¬(s) + 2AgNO3(aq) → 2Ag(s) + Zn(NO3)2 (aq). How many grams of silver are produced?

• Chemistry, not "college" -

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• chemistry -

Calculate the heat of formation of water from its constituent elements from the following information:

3 H2 (g) + O3 (g) → 3H2O ∆H = ?
2 H2 (g) + O2 (g) → 2H2O ∆H = - 483.6
3 O2 (g) → 2O3 (g) ∆H = 284.5

You are given 2.0 grams of zinc and 2.5 grams of silver nitrate and are told they react in the following manner: Zn¬(s) + 2AgNO3(aq) → 2Ag(s) + Zn(NO3)2 (aq). How many grams of silver are produced?

• chemistry -

#1 makes no sense. You have the heat of formation from the constituent elements listed in your question and the question marks by a reaction that is not the formation of water from its constituent elements.
#2.
Write the equation.
Convert 2 g Zn to moles.
Convert 2.5 g AgNO3 to mols.
Using the coefficients in the balanced equation, convert each of the moles into moles of any one (I suggest Ag) of the products.
The smaller number of moles of product formed from either of the reactants will be the limiting reagent; therefore, that will be the number of grams Ag produced. Post your work if you get stuck.

• college -

2.0g Zn= 0.0305mol 2.5gAgNO3 =0.0147mol

I am stuck after this. I cannot come to the correct answer.