Answer:
(a) (i) All the elements of a group have similar chemical properties because they have same no. of valence electrons in their outermost shell. (ii) All the elements of a period have different chemical properties because they have different no. of valence electrons in their atoms.
Answer:
This is the balanced equation:
Pb(NO₃)₂ (aq) + 2NaI (aq) → 2NaNO₃ (aq) + PbI₂ (s) ↓
Explanation:
This are the reactants:
PbNO₃
NaI
Iodide can react to Pb²⁺ to make a solid compound.
Magnesium(?)
<span>2 HCl + Mg ? MgCl2 + H2</span>
1) Formulas:
a) mole fraction of component 1, X1
X1 = number of moles of compoent 1 / total number of moles
b) Molar mass = number grams / number of moles => number of moles = number of grams / molar mass
2) Application
Number of moles of CaI2 = 0.400
Molar mass of water = 18.0 g/mol
Number of moles of water: 850.0 g / 18.0 g/mol = 47.22 mol
Total number of moles = 0.400 + 47.22 =47.62
Molar fraction of CaI2 = 0.400 / 47.62 = 0.00840
