Step 1: Calculate the molar mass of K₂Cr₂O₇.
The molar masses of K, Cr, and O are 39.10 g, 52.00 g, and 16.00 g, respectively.
[tex]\begin{aligned} \text{molar mass} & = \text{2(39.10 g) + 2(52.00 g) + 7(16.00 g)} \\ & = \text{294.2 g} \end{aligned}[/tex]
Step 2: Calculate the mass of K₂Cr₂O₇ by using dimensional analysis.
[tex]\begin{aligned} \text{mass of} \: \text{K}_2\text{Cr}_2\text{O}_7 & = 4.56 \times 10^{24} \: \text{formula units} \: \text{K}_2\text{Cr}_2\text{O}_7 \times \frac{\text{1 mol} \: \text{K}_2\text{Cr}_2\text{O}_7}{6.022 \times 10^{23} \: \text{formula units} \: \text{K}_2\text{Cr}_2\text{O}_7} \times \frac{\text{294.2 g} \: \text{K}_2\text{Cr}_2\text{O}_7}{\text{1 mol} \: \text{K}_2\text{Cr}_2\text{O}_7} \\ & = \boxed{2.23 \times 10^3 \: \text{g}} \end{aligned}[/tex]
Hence, there are 2.23 × 10³ g present in 4.56 × 10²⁴ formula units of K₂Cr₂O₇.
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SOLUTION:
Step 1: Calculate the molar mass of K₂Cr₂O₇.
The molar masses of K, Cr, and O are 39.10 g, 52.00 g, and 16.00 g, respectively.
[tex]\begin{aligned} \text{molar mass} & = \text{2(39.10 g) + 2(52.00 g) + 7(16.00 g)} \\ & = \text{294.2 g} \end{aligned}[/tex]
Step 2: Calculate the mass of K₂Cr₂O₇ by using dimensional analysis.
[tex]\begin{aligned} \text{mass of} \: \text{K}_2\text{Cr}_2\text{O}_7 & = 4.56 \times 10^{24} \: \text{formula units} \: \text{K}_2\text{Cr}_2\text{O}_7 \times \frac{\text{1 mol} \: \text{K}_2\text{Cr}_2\text{O}_7}{6.022 \times 10^{23} \: \text{formula units} \: \text{K}_2\text{Cr}_2\text{O}_7} \times \frac{\text{294.2 g} \: \text{K}_2\text{Cr}_2\text{O}_7}{\text{1 mol} \: \text{K}_2\text{Cr}_2\text{O}_7} \\ & = \boxed{2.23 \times 10^3 \: \text{g}} \end{aligned}[/tex]
Hence, there are 2.23 × 10³ g present in 4.56 × 10²⁴ formula units of K₂Cr₂O₇.