The answer is D. It may gain or lose electrons.
Iron fillings can be separated as they are magnetic. Use a magnet to separate the iron fillings away.
Salt can be separated away as they are soluble in water.
The answer is: B) it has decreased.
Answer:81.6%
Explanation:
Mass of CaCO3=4.010 g
Molar mass of CaCO3= 40+12+(16×3) = 100 g/mol.
Recall: number of moles(n)= mass÷ molar mass.
n=4.010÷100 = 0.0401 mol.
Molar mass of CaCl2 = 40+71= 111 g/mol.
Number of mol of CaCl2 = 5.455÷111= 0.04914 g/mol.
Mass of CaCl2 = 0.0401 × 111 = 4.4511 g of CaCl2.
Percent by mass of CaCl2 = (4.4511÷5.455) × 100
= 0.815967 ×100 = 81.5967%
Approximately; 81.6%.