Answer:
C₂ = 0.056 ppm
Explanation:
Given data:
Initial volume = 2.0 mL
Initial concentration = 7.0 ppm
Final volume = 250.0 mL
Final concentration = ?
Solution:
Formula:
C₁V₁ = C₂V₂
C₁ = Initial concentration
V₁ = Initial volume
C₂ = Final concentration
V₂ = Final volume
Now we will put the values in formula.
C₁V₁ = C₂V₂
7.0 ppm × 2.0 mL = C₂ × 250.0 mL
C₂ = 14.0 ppm.mL /250.0 mL
C₂ = 0.056 ppm
When two aqueous solutions are mixed together and the temperature of the solution decreases, the reaction is called an endothermic reaction with a positive enthalpy change. Endothermic reaction is when heat is absorbed by the reaction taking place. All endothermic reaction always have a positive enthalpy change.
Answer:
Explanation:
1. Write the equation for the reaction.
M_r: 24.30
MgCl₂ ⟶ Mg + Cl₂
m/g: 60.0
2. Calculate the moles of Mg
Moles of Mg = 60.0 g Mg × (1 mol Mg/ 24.30 g Mg) = 2.469 mol Mg
3. Calculate the moles of electrons
Moles of electrons = 2.469 mol Mg × (2 mol electrons/1 mol Mg)
= 4.938 mol electrons
4. Calculate the number of coulombs
Q = 4.938 mol electrons × (96 485 C/1 mol electrons) = 476 500 C
5. Calculate the current required
Q = It
I = Q/t
t = 2.00 h × (60 min/1h) × (60 s/1 min) = 7200 s
I = 476 500 C/7600 s= 66.2 C/s = 66.2 A
You need a current of 
.
When you change the number of protons in an atom, you will change the atom from one element to a different element. Sometimes, when you add a proton to an element, the element will become radioactive. If you change the number of electrons in an atom, you will get an ion of the element.
