There are several differences between<span> a </span>physical and chemical change<span> in matter or substances. A </span>physical change<span> in a substance doesn't </span>change<span> what the substance is. In a </span>chemical change<span> where there is a </span>chemical<span> reaction, a new substance is formed and energy is either given off or absorbed.</span>
The chemical equation without coefficients is:
Ca + CO2 + O2 --------> Ca CO3
You can balance that equation by trial an error.
This is the chemical equation balanced:
2Ca + 2CO2 + O2 --------> 2Ca CO3
Count the atoms on each side to check the balance
Atom Left side right side
Ca 2 2
C 2 2
O 2*2 + 2 = 6 2*3 = 6
Then those are the coefficients:
a0 = 2
a1 = 2
a2 = 1
a3 = 2
The magnesium dissolves to form magnesium chloride and hydrogen gas is released.
Mg + 2HCl -----> MgCl2 + H2(g).
The reaction produces 2.93 g H₂.
M_r: 133.34 2.016
2Al + 6HCl → 2AlCl₃ + 3H₂
<em>Moles of AlCl₃</em> = 129 g AlCl₃ × (1 mol AlCl₃/133.34 g AlCl₃) = 0.9675 mol AlCl₃
<em>Moles of H₂</em> = 0.9675 mol AlCl₃ × (3 mol H₂/2 mol AlCl₃) = 1.451 mol H₂
<em>Mass of H₂</em> = 1.451 mol H₂ × (2.016 g H₂/1 mol H₂) = 2.93 g H₂
Answer:D and C sorry if im wrong
Explanation:
