how many moles of Li in 3g?
write the reaction equation.
It will tell you how many moles of H2 will be produced for each mole of Li
convert to grams for mass
each mole occupies 22.4L at STP
If you use a 3g piece of lithium to react with an excess of water, calculate the mass and volume of hydrogen gas that was prepared
2 answers
2Li(s)+2H2O(l)->2LiOH(aq)+H2(g)
RAM of Li=7
moles of Li=3/7 moles
mole ratio of Li to H2 is 2:1
moles of H2 =1/2×3/7=3/14 moles
mass=moles×molar mass
=3/14×2
=0.429g
1mole at STP= 22.4dm^3
3/14moles=??
=3/14×22.4
=4.8dm^3
RAM of Li=7
moles of Li=3/7 moles
mole ratio of Li to H2 is 2:1
moles of H2 =1/2×3/7=3/14 moles
mass=moles×molar mass
=3/14×2
=0.429g
1mole at STP= 22.4dm^3
3/14moles=??
=3/14×22.4
=4.8dm^3
3 answers