If one or more of the following occur: Gas formation, precipitate formation, color change, temperature change, or odor
I think if was chemical energy hope I helped
Answer: 31 (a) 4 32 (a) 5
(b) 7 (b) 3
(c) 5 (c) 5
(d) 3 (d) 2
<u>Significant Figures (sf) Rules:</u>
1) Trailing zeroes are considered significant ONLY If a decimal point is provided.
2) Zeroes between the decimal point and number are NOT significant <u>unless</u> they are between numbers.
3) All digits in scientific notation are counted (disregard the exponent).
31 (a) 508.0 <em>trailing zero so use rule 1 </em> --> sf = 4
(b) 820,400.0 <em>trailing zero so use rule 1 </em> --> sf = 7
(c) 1.0200 x 10⁵ <em>scientific notation so use rule 3</em> --> sf = 5
(d) 807,000 <em>no trailing zeroes so use rule 1</em> --> sf = 3
32 (a) 0.049450 <em>zero between decimal point & #, use rule 2</em> --> sf = 5
(b) 0.000482 <em>zero between decimal point & #, use rule 2</em> --> sf = 3
(c) 3.1587 x 10 ⁻⁸ <em>scientific notation so use rule 3</em> --> sf = 5
(d) 0.0084 <em>zero between decimal point & #, use rule 2</em> --> sf = 2