Answer: " 145,000 g " .
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Explanation:
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To solve: Let's use a technique known as "dimensional analysis"
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[tex]\frac{287.34 g}{mol}[/tex] * ( 537 mol) = ? g ;
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Note: "g" stands for "grams" ;
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The units of "mol" ["mole(s)"] on the "left-hand side of the equation"
→ "cancel out" ; {since: "mol/mol" = 1 "} ;
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And we have:
(287.34 * 537) g ;
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Using a calculator, we do the multiplication to get:
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154301.58 g ; We round this to 3 (three) significant figures;
since: (287.34 * 537) g ; the limiting number with the "least number of significant figure" is "537" ; which has 3 (three) significant figures;
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As such:
We have 154301.58 g ;
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We round this to 145,000 g ; since:
"154" are the first 3 (three) significant figures in our value:
" 154301.58" ; and the next significant figure, "3" ; is less than "5" ;
If the next significant figure were "0, 1, 2, 3, or 4" ; we would round down to: 145,000 g; such as in our case. If the next significant figure were "5, 6, 7, 8, or 9" , we would round up to: 146,000 g .
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The correct answer is: " 145,000 g ."
