Get expert insights and community support for your questions on IDNLearn.com. Our platform provides trustworthy answers to help you make informed decisions quickly and easily.

How many grams of water will be produced if you start with 4.0 grams of hydrogen and an excess of oxygen given the following balanced chemical equation?

2H2 + O2 → 2H2O

Group of answer choices

A. 32.0 grams

B. 36.0 grams

C. 54.0 grams

D. 18.0 grams


Sagot :

Answer:

B.) 36.0 grams

Explanation:

To find the mass of water, you need to (1) convert grams H₂ to moles (using the molar mass), then (2) convert moles H₂ to moles H₂O (using mole-to-mole ratio from reaction coefficients), and then (3) convert moles H₂O to grams (using the molar mass). It is important to arrange the conversions in a way that allows for the cancellation of units.

Molar Mass (H₂): 2(1.008 g/mol)

Molar Mass (H₂): 2.016 g/mol

Molar Mass (H₂O): 2(1.008 g/mol) + 15.998 g/mol

Molar Mass (H₂O): 18.014 g/mol

2 H₂ + O₂ -----> 2 H₂O
^                        ^

4.0 g H₂            1 mole             2 moles H₂O           18.014 g
---------------  x  ----------------  x  ------------------------  x  ---------------  = 36 g H₂O
                          2.016 g             2 moles H₂              1 mole