Answer:
5.37 × 10⁻⁴ mol/L
Explanation:
<em>A chemist makes 660. mL of magnesium fluoride working solution by adding distilled water to 230. mL of a 0.00154 mol/L stock solution of magnesium fluoride in water. Calculate the concentration of the chemist's working solution. Round your answer to 3 significant digits.</em>
Step 1: Given data
- Initial concentration (C₁): 0.00154 mol/L
- Initial volume (V₁): 230. mL
- Final concentration (C₂): ?
- Final volume (V₂): 660. mL
Step 2: Calculate the concentration of the final solution
We want to prepare a dilute solution from a concentrated one. We can calculate the concentration of the final solution using the dilution rule.
C₁ × V₁ = C₂ × V₂
C₂ = C₁ × V₁ / V₂
C₂ = 0.00154 mol/L × 230. mL / 660. mL = 5.37 × 10⁻⁴ mol/L
Answer:
Number of moles = 0.92 mol
Explanation:
Given data:
Mass of CaSO₄ = 125 g
Number of moles of CaSO₄ = ?
Solution:
Formula:
Number of moles = mass/ molar mass
Molar mass of CaSO₄:
Molar mass of CaSO₄ = 40 + 32+ 16×4
Molar mass of CaSO₄ = 40 + 32+ 64
Molar mass of CaSO₄ = 136 g/mol
Number of moles:
Number of moles = mass/ molar mass
Number of moles = 125 g/ 136 g/mol
Number of moles = 0.92 mol
The answer is d because in both sides there are 1 magnesiums 1 oxygens 2 lithiums and 2 chlorines
Explanation:
It happens because particles of gas are in constant random motion. Thus they can collide with the walls of the container causing pressure on the walls.
