Answer:
I don't know if this is right but try it. The amount of water vapor in the air is called absolute humidity. The amount of water vapor in the air as compared with the amount of water that the air could hold is called relative humidity. This amount of space in air that can hold water changes depending on the temperature and pressure.
We have to know the molarity of solution obtained when 5.71 g of Na₂CO₃.10 H₂O is dissolved in water and made up to 250 cm³ solution.
The molarity of solution obtained when 5.71 g of sodium carbonate-10-water (Na₂CO₃.10 H₂O) is dissolved in water and made up to 250.0 cm^3 solutionis: (A) 0.08 mol dm⁻³
The molarit y of solution means the number of moles of solute present in one litre of solution. Here solute is Na₂CO₃.10 H₂O and solvent is water. Volume of solution is 250 cm³.
Molar mass of Na₂CO₃.10 H₂O is 286 grams which means mass of one mole of Na₂CO₃.10 H₂O is 286 grams.
5.71 grams of Na₂CO₃.10 H₂O is equal to 
= 0.0199 moles of Na₂CO₃.10 H₂O. So, 0.0199 moles of Na₂CO₃.10 H₂O present in 250 cm³ volume of solution.
Hence, number of moles of Na₂CO₃.10 H₂O present in one litre (equal to 1000 cm³) of solution is 
= 0.0796 moles. So, the molarity of the solution is 0.0796 mol/dm³ ≅ 0.08 mol/dm³
Answer:
26 grams of D will be produced.
Explanation:
The reaction is given by:
A + B -----> C + D
Mass of A reacted = 21 g
Mass of B reacted = 22 g
Mass of C formed = 17 g
Mass of D formed = m =?
According to law of conservation of mass, the total mass of the reactants used is equal to the total mass of the product formed.
Then:
mass of A reacted + mass of B reacted = mass of C formed + mass of D formed
21 + 22 = 17 + m
m = 26 g
Answer:
16 is the mass number. 8 is the atomic number.
