Answer:
Molar mass Na2CO3 = 2*23 + 12 + 3*16 = 106 g/ mol
Mass of 1 mol Na2CO3 = 106 g
mass (Na2CO3) = 106g*250cm³/1000cm³ = 26.5 g
1) It is necessary because all Na2CO3 will be in the solution, and no Na2CO3 would be lost.
2) Because the solution that was formed after rinsing beaker contains Na2CO3.
3) Eyes should be on the level of calibration mark of the volumetric flask.
4) It is necessary to prevent evaporation of water, and changing , because of it, the concentration of the solution.
We calculate for the number of moles of water given its mass by dividing the given mass by the molar mass.
n water = (36.04 g) / (18 g/mol)
n water = 2 mols
From the given balanced equation, every 6 moles of water produced will require 7 moles of oxygen.
n oxygen = (2 mols H2O) x (7 moles O2 / 6 moles H2O)
n oxygen = 2.33 mols O2
Answer:
energy known as the latent heat of vaporization is required to break the hydrogen bonds. At 100 °C, 540 calories per gram of water are needed to convert one gram of liquid water to one gram of water vapour under normal pressure.
Explanation:energy known as the latent heat of vaporization is required to break the hydrogen bonds. At 100 °C, 540 calories per gram of water are needed to convert one gram of liquid water to one gram of water vapour under normal pressure.
Answer:
the oxidation number is zero because H=+1. S=-2
Explanation:
so two hydrogen and one sulphur so total no is zero
