chemistry warm-up question

[naithgirw]

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If 1 mole of Hydrogen and 1 mole of Oxygen are mixed and allowed to react according to the equation:

2 moles of hydrogen plus 1 mole of oxygen yeilds 2 moles of water,

the maximum number of moles of water that could be produced is...

A) 2/3
B) 3/2
C) 2/1
D) 1/2
E) 1/1

 

[dentwannabe]

If 1 mole of Hydrogen and 1 mole of Oxygen are mixed and allowed to react according to the equation:

2 moles of hydrogen plus 1 mole of oxygen yeilds 2 moles of water,

the maximum number of moles of water that could be produced is...

A) 2/3
B) 3/2
C) 2/1
D) 1/2
E) 1/1

Ok, based on my work, the answer should be E. 1 mol H20

Here's how I went about it.. they tell you u mix 1 mol H and 1 mol O2 (or O.. im not sure how u'd write it.. but it doesnt matter in this case)

and the equation is 2H + 1O2 --> 2H20

so they want to know the MAX. formed.. so find the one that is NOT the limiting reagent..

1molH * 2molH20/2molH = 1 mol H20 formed
if you use O2, u get
1molO2 * 2mol H20/1molO2 = 2 mol H20

its basic stoichiometry..
From what I calculated, H is the limiting reagent.. so the max. water you can get is with that.. cuz once you run out of H, no more water.

Therefore, the answer is 1/1 mol H20, E

 

[naithgirw]

I also chose E too! Well Done!

we are given 1 mole of H2 and 1 mole of O2, and the following equation:

2H2 + O2 --> 2H2O
(2 moles of hydrogen plus one mole of oxygen react to form 2 moles of water)

according to the above equation, and what we are given, I believe the limiting reagant (what we run out of first, and therefore limits the quantity of product) is hydrogen

my reasoning: the one mole of hydrogen will run out first (no calculation required), because it will only react with .5 mol Oxygen! And that leaves .5 Oxygen unreacted!

To get to the point, 1 mol of hydrogen reacts with .5 mol oxygen to yield 1 mol of water! Answer is choice E) 1/1

In actuality - this question should take no longer than about 4-5 seconds to answer, it is a practice question from a DAT sample test! The more we practice - the faster we will be!

Keep it up guys!

 

[dentwannabe]

I also chose E too! Well Done!

we are given 1 mole of H2 and 1 mole of O2, and the following equation:

2H2 + O2 --> 2H2O
(2 moles of hydrogen plus one mole of oxygen react to form 2 moles of water)

according to the above equation, and what we are given, I believe the limiting reagant (what we run out of first, and therefore limits the quantity of product) is hydrogen

my reasoning: the one mole of hydrogen will run out first (no calculation required), because it will only react with .5 mol Oxygen! And that leaves .5 Oxygen unreacted!

To get to the point, 1 mol of hydrogen reacts with .5 mol oxygen to yield 1 mol of water! Answer is choice E) 1/1

In actuality - this question should take no longer than about 4-5 seconds to answer, it is a practice question from a DAT sample test! The more we practice - the faster we will be!

Keep it up guys!

um, ok Coach!!

 

[naithgirw]

um, ok Coach!!

I didn't mean to be cocky or anything, but after re-reading my own post, I did sense that I was giving off the impression that I am a 'Mr. Know It All'. I'm glad you saw the humor in it though! 🙂