Answer:
mNaCl = mNa + mCl
mNa = 20g
mCl = mCl2/2 = 30/2 = 15g
mNaCl= 20+15 = 35g
630g
Explanation:
firstly the equation has to be balanced. 2H2+o2>2H2o.
finding the mole of hydrogen?
mole = 70/2 which is equal to 35 mole of hydrogen.
35 mole of hydrogen is equal to the mole of water.
finding the mass of water=?
35=mass/18
mass= 35*18=630g of water
Answer : The mass of reactant
remain would be, 0.20 grams.
Solution : Given,
Moles of
= 0.40 mol
Moles of
= 0.15 mol
Molar mass of
= 2 g/mole
First we have to calculate the limiting and excess reagent.
The balanced chemical reaction is,

From the balanced reaction we conclude that
As, 1 mole of
react with 2 mole of 
So, 0.15 moles of
react with
moles of 
From this we conclude that,
is an excess reagent because the given moles are greater than the required moles and
is a limiting reagent and it limits the formation of product.
The moles of reactant
remain = 0.40 - 0.30 = 0.10 mole
Now we have to calculate the mass of reactant
remain.


Therefore, the mass of reactant
remain would be, 0.20 grams.
Answer:
Explanation: you need to remove the subscript of 5