Answer:
Mass = 6.538 g
Explanation:
Given data:
Mass of zinc hydroxide produced = 9.65 g
Mass of zinc required = ?
Solution:
Chemical equation:
Zn + 2MnO₂ + H₂O → Zn(OH)₂ + Mn₂O₃
Number of moles of zinc hydroxide:
Number of moles = mass/molar mass
Number of moles = 9.65 g/ 99.42 g/mol
Number of moles = 0.1 mol
now we will compare the moles of zinc and zinc hydroxide,
Zn(OH)₂ : Zn
1 : 1
0.1 : 0.1
Mass of zinc required:
Mass = number of moles × molar mass
Mass = 0.1 mol × 65.38 g/mol
Mass = 6.538 g
Answer:
0.1 M
Explanation:
The following data were obtained from the question:
Initial volume (V1) = 100 mL
Initial concentration (C1) = 0.5 M
Final volume (V2) = 500 mL
Final concentration (C2) =?
Using the dilution formula C1V1 = C2V2, the new concentration of the solution can be obtained as follow:
C1V1 = C2V2
0.5 × 100 = C2 × 500
50 = C2 × 500
Divide both side by 500
C2 = 50/500
C2 = 0.1 M
Therefore, the new concentration of the solution is 0.1 M
Answer/Explanation:
Chlorine and Fluorine are in the Halogen family. The elements in the Halogen family are:
Fluorine (F)
Chlorine (Cl)
Bromine (Br)
Iodine (I)
Astatine (At)
Tennessine (Ts)
Hydrogen (H) is a nonmetal
Oxygen (O) is a nonmetal
Lithium (Li) is an alkaline metal.
We are going to use Avogadro's constant to calculate how many molecules of
carbons dioxide exist in lungs:
when 1 mole of CO2 has 6.02 x 10^23 molecules, so how many molecules in
CO2 when the number of moles is 5 x 10^-2
number of molecules = moles of CO2 * Avogadro's number
= 5 x 10^-2 * 6.02 x 10^23
= 3 x 10^22 molecules
∴ There are 3 x 10^22 molecules in CO2 exist in lungs