In the explosion of a hydrogen-filled balloon, 0.80 g of hydrogen reacted with 6.4 g of oxygen. how many grams of water vapor are formed? (water vapor is the only product.)

 0.4 moles H2O x (18.0 g / mole) = 7.2 g H2O

Explanation:

write the values given in the question

In an explosion of hydrogen balloon, 0.80g of hydrogen is reacted with 6.4g of oxygen.

Write the balanced equation

2 H2 + O2 ---> 2 H2O

0.80 g H2 x (1 mole / 2g) = 0.4 moles H2

6.4 g O2 x (1 mole / 32g) = 0.2 moles O2

from balanced equation, 2 moles H2 react with 1 mole O2

therefore

0.4 moles H2 x (1 mole O2 / 2 moles H2) = 0.2 moles O2

since we need 0.2 moles O2 to react with all the H2 and we have exactly that amount, the amounts are said to be

"stoichiometric" and either reactant can be considered limiting

from the balanced equation, 2 moles H2 --> 2 moles H2O.. therefore

0.4 moles H2 x (2 moles H2O / 2 moles H2) = 0.4 moles H2O

Then

0.4 moles H2O x (18.0 g / mole) = 7.2 g H2O

a non redox reaction occurs when there is not a transfer of electrons. for redox reactions, which are reduction-oxidation reactions, a change in the oxidation number occurs. elements that are reduced gain electrons, and elements that are oxidized lose electrons.

explanation:

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.