What is the final volume of a sample of neon under 5.6 atm of pressure at 250 k if it was initially at 6.7 atm or pressure, 500k
2 answers:
You might be interested in
Answer:
% purity of limestone = 96.53%
Explanation:
Question (4).
Weight of impure CaCO₃ = 25.9 g
Molecular weight of CaCO₃ = 40 + 12 + 3(16)
= 100 g per mole
We know at S.T.P. number of moles of CO₂ = 1 and volume = 22.4 liters
From the given reaction, 1 mole of CaCO₃ reacts with 1 mole or 22.4 liters of
CO₂.
∵ 22.4 liters of CO₂ was produced from CaCO3 = 100 g
∴ 1 liter of CO₂ will be produced by CaCO₃ =
∴ 5.6 liters of CO₂ will be produced by CaCO₃ =
= 25 g
Therefore, % purity of CaCO₃ =
=
= 96.53 %
Answer:
1.155 moles of potassium nitrate are required to make 550 mL of a 2.1M solution.
Explanation:
In a mixture, the chemical present in the greatest amount is called a solvent, while the other components are called solutes.
Molarity is a unit of concentration of a solution and indicates the amount of moles of solute that appear dissolved in each liter of the mixture. In other words, the Molarity (M) or Molar Concentration is the number of moles of solute that are dissolved in a given volume.
The Molarity of a solution is determined by the following expression:
Molarity is expressed in units ().
In this case:
- Molarity= 2.1 M
- number of moles of solute= ?
- Volume= 550 mL= 0.550 L (being 1L=1000 mL)
Replacing:
Solving:
number of moles of solute= 2.1 M* 0.550 L
number of moles of solute= 1.155 moles
1.155 moles of potassium nitrate are required to make 550 mL of a 2.1M solution.