Question

1. consider the chemical formula for one molecule of ethanol, c₂h₅oh. if instead of one molecule of ethanol we had 5, how many hydrogen atoms would be present? (1pts) 30 25 10 6 16) what is the total number of atoms present in al₂(cr₂o₇)₃? (1pts) 11 20 27 29

Explanation:

Step1: Count atoms in $\text{Al}_2(\text{Cr}_2\text{O}_7)_3$

Step1a: Calculate Al atoms

$2$ (from subscript of Al)

Step1b: Calculate Cr atoms

$2 \times 3 = 6$

Step1c: Calculate O atoms

$7 \times 3 = 21$

Step1d: Sum all atoms

$2 + 6 + 21 = 29$

Step2: Calculate H atoms in 5 ethanol

Step2a: H per ethanol molecule

$5 + 1 = 6$ (from $\text{C}_2\text{H}_5\text{OH}$)

Step2b: Total H atoms

$6 \times 5 = 30$

Answer:

1. $\boldsymbol{29}$
2. $\boldsymbol{30}$