There are 8 valence electrons in the Kr atom, this is because Krypton is in the 8th group. Krypton is in the far right row of the periodic table, making it the outermost shell (which is 8 valence electrons)
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<span>Answer
is: mass of burned butane is 11.6 g.</span>
Chemical reaction: 2C₄H₁₀ + 13O₂ → 8CO₂ + 10H₂O.
m(butane)
= 50,0 g.
<span>
V(CO</span>₂) = 17,9 L.<span>
n(CO</span>₂) = V(CO₂) ÷
Vm.<span>
n(CO</span>₂) = 17,9 L ÷ 22,4 L/mol.<span>
n(CO</span>₂) = 0,8 mol.<span>
From chemical reaction n(CO</span>₂) :
n(C₄H₁₀) = 8 : 2.<span>
n(C</span>₄H₁₀) =
0,8 mol ÷ 4.<span>
n(C</span>₄H₁₀) =
0,2 mol.<span>
m(C</span>₄H₁₀) =
n(C₄H₁₀) · M(C₄H₁₀).<span>
m(C</span>₄H₁₀) =
0,2 mol · 58 g/mol.<span>
m(C</span>₄H₁₀) =
11,6 g.
Given the reaction 2Pb(s)+O2(g)= 2PbO(s) and a reactant amount of 451.4 grams, we are asked for the yield of the reaction. The amount of lead present produces 451.4/207.2 *( 2/2) *(223.2) via 100% conversion, 486.26 grams lead (II) oxide. hence the percent yield is 356.7g /<span>486.26 g or equal to 73.35 percent</span>