Answer:
Copper turns green on exposure to air
Explanation:
Liquid water freezes to form ice: Physical change
Reason: Water can melt back when it becomes ice.
Copper turns green on exposure to air: Chemical change
Reason: The copper can not change back from the green state when it turns green.
In france grapes are 1.83 euros per kilogram. What is the cost of grapes in dollars per pound if the exchange rate is 1.40 dollars per euro
1.83 euros x 1.40 = 2.56 dollars
1 pound = 0.454 kilogram
1.83 euros per kilogram = 2.56 x 0.454 = 1.16 dollars per pound
Slavery played a big role in this. the confederacy allowed slavery while the union was oppose to it.
Balanced chemical reaction:
MgSO₄(aq) + Sr(NO₃)₂(aq) → Mg(NO₃)₂(aq) + SrSO₄(s).
Ionic reaction:
Mg²⁺(aq) + SO₄²⁻(aq) + Sr²⁺(aq) + 2NO₃⁻(aq) → Mg²⁺(aq) + 2NO₃⁻(aq) + SrSO₄(s).
Net ionic reaction:
Sr²⁺(aq) + SO₄²⁻(aq) → SrSO₄(s).
Magnesium sulfate (MgSO₄), strontium nitrate (Sr(NO₃)₂ and magnesium nitrate (Mg(NO₃)₂) are soluble in water. Strontium sulfate (SrSO₄) is not soluble in water.
This chemical reaction is double displacement reaction - cations and anions of the two reactants switch places and form two new compounds.
