NaH(s)+ H2O (l)=>NaOH(aq)+H2(g)
You want to calculate the mass of NaH, I assume. Otherwise, the question isn't clear. It simply says calculate the mass(??)
So, calculate the moles of H2 gas that satisfy the conditions of 982 ml at 28ºC and 765 torr. But you must subtract the vapor pressure of water at 28º to get the actual pressure of the H2 gas. So, the actual conditions are 982 ml (0.982 L) and 301 K and 765-28 = 737 torr.
PV = nRT
n = PV/RT = (737 torr)(0.982 L)/(62.4 L-torr/Kmol)(301 K)
n = 0.0385 moles H2
moles NaH needed = 0.0385 moles H2 x 1 mole NaH/mole H2 = 0.0385 moles NaH required
mass of NaH needed = 0.0385 moles x 24 g/mole = 0.925 g NaH
Brainliest Please :)
So I haven’t got time to answer all of it for you but the id you look at the picture of the periodic table I’ve added the top number in the red boxes are the groups and the period is how many elements down from the top it is (remember that the hydrogen and helium make up period ONE) so remember to include them when counting the elements as you go down the table
The textbook would lose potential energy since its falling from a high height.
Answer:
Given : Diatomic molecule at 273K
'q' absorbed = positive = +100Cal = 100 x 4.184J = 418.4J
'W' done by system = negative = -209J
By first law of thermodynamics;
ΔU = q + W = 418.4 + (-209) = 209.4J
We know for diatomic molecule Cv=25R and CvΔT=ΔU
CvΔT=209.4
25RΔT=209.4
ΔT=5R209.4×2
And, Heat exchange=Cm×ΔT
where; Cm is molar heat capacity
Cm=ΔTHeat Exchange
substituting values for Heat Exchange = 418.4 and ΔT=5R209.4×2
Cm=5R
