I have a chemistery question.?

Question

Hey,I am desperately trying to solve this exercise but I cannot.I really hope someone can help me.

A potential fuel for rockets is a combination of  B little 5 H little 9 and O little 2. The act react according to the following balanced equation: 

2B little 5 H little  (l)  plus 12 O little 2 arrow 5 B little 2 O little 3 (s) plus 9H little 2 O (g)

If one tank in  a rocket holds  holds 126 g  B little 5 H little 9  and another tank holds 192 grams O little 2,what mass off water can be produced when the entire contents of each tank react together?

I apologize for the notation.An answer would be very much appreciated. 
Maxim

I know nothing · Accepted Answer

jesus christ I have never seen that notation before. I'll write it out how it's supposed to be so I don't get confused (in future, just write it out this way. People will know what you're talking about):
B5H9 and O2 will react in the following way:

2B5H9 (l) + 12O2 --> 5B2O3 (s) + 9H2O (g)

Well you need to calculate the number of moles of each reactant and find out which one is the limiting factor. B5H9 has a molar mass of 63.055g/mol (from the periodic table) so 126g/63.055g/mol = 2 moles

the molar mass of O2 is 32g/mol so 192g/32g/mol = 6 moles

So you have 2 moles of B5H9 and 6 moles of O2 reacting. That means that you can actually only have 1 mole of B5H9 reacting if you look at the stoichiometry in your balanced reaction equation (6 moles of 12O2 means only half of the equation will actually take place)

Looking at your chemical reaction again, it is meant to produce 9 waters. Since only half the reaction is taking place, you will produce only 3.5 moles of water. 
So the molar mass of water is 34g/mol so 34*3.5 = 119g of water = 119mL

I have a chemistery question.?

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