The rule of significant figures when multiplying numbers is that the number of significant figures of the product must be that of the least number of significant figures of the factors.
The factors are 2.2 which has 2 significant figures and 5.00 which has 3 significant figures. Therefore, the product must only have 2 significant figures.
The answer is B. 11 mm2
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
“Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons.”
https://www.chemguide.co.uk/atoms/bonding/electroneg.html
^this link may help you understand. Good luck!
Answer - Pure water
Reasoning - Can be stirred into the water to form homogeneous :).