Question

what compound contains the highest percent composition of cobalt? \\(\ce{co(no_3)_3}\\) \\(\ce{co(no_3)_3}\\) \\(\ce{co(no_3)_3}\\) \\(\ce{co(no_3)_3}\\) \\(\text{no.}\\) choose the best answer. campers plan to make smores around the campfire using the following recipe: 1 marshmallow + 2 graham crackers + 3 pieces of chocolate \\(\
ightarrow\\) 1 smore they brought a bag of 28 marshmallows, a box of graham crackers containing 28 crackers, and 4 chocolate bars with 12 pieces in each bar. what is the limiting reactant? graham crackers chocolate marshmallow smore \\(\text{nr1.}\\) choose the best answer. avogadros number has a constant value of ——. 273.15 12.011 \\(6.02 \times 10^{23}\\) \\(6.63 \times 10^{-34}\\)

Explanation:

Step1: Calculate % Co for $\text{Co(NO}_3\text{)}_3$

Molar mass of $\text{Co(NO}_3\text{)}_3$: $58.93 + 3\times(14.01 + 3\times16.00) = 244.96$ g/mol
$\% \text{Co} = \frac{58.93}{244.96} \times 100\% \approx 24.06\%$

Step2: Calculate % Co for $\text{Co(NO}_3\text{)}_2$

Molar mass of $\text{Co(NO}_3\text{)}_2$: $58.93 + 2\times(14.01 + 3\times16.00) = 182.95$ g/mol
$\% \text{Co} = \frac{58.93}{182.95} \times 100\% \approx 32.21\%$

Step3: Calculate % Co for $\text{Co(NO}_2\text{)}_3$

Molar mass of $\text{Co(NO}_2\text{)}_3$: $58.93 + 3\times(14.01 + 2\times16.00) = 196.96$ g/mol
$\% \text{Co} = \frac{58.93}{196.96} \times 100\% \approx 29.92\%$

Step4: Calculate % Co for $\text{Co(NO}_2\text{)}_2$

Molar mass of $\text{Co(NO}_2\text{)}_2$: $58.93 + 2\times(14.01 + 2\times16.00) = 150.95$ g/mol
$\% \text{Co} = \frac{58.93}{150.95} \times 100\% \approx 39.04\%$

Step5: Find max s'mores from marshmallows

1 marshmallow makes 1 s'more. 28 marshmallows → $28 \times 1 = 28$ s'mores

Step6: Find max s'mores from graham crackers

2 crackers make 1 s'more. 28 crackers → $\frac{28}{2} = 14$ s'mores

Step7: Find max s'mores from chocolate

Total chocolate pieces: $4 \times 12 = 48$. 3 pieces make 1 s'more → $\frac{48}{3} = 16$ s'mores

Step8: Identify limiting reactant

The smallest number of s'mores determines the limiting reactant.

Step9: Recall Avogadro's number definition

Avogadro's number is the number of particles in 1 mole.

Answer:

1. $\text{Co(NO}_2\text{)}_2$
2. graham crackers
3. $6.02 \times 10^{23}$