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When it comes to gases, understanding how many moles you have can be crucial. A mole is a way to count particles, much like a dozen counts items by twelves. The number of moles can be found from various gas properties using the Ideal Gas Law. The problem provides volume (1.72 L), pressure (743 torr), and temperature (28掳C) for carbon dioxide (CO鈧�). Before calculating moles, we need to get those units right. Convert the temperature to Kelvin by adding 273.15 to Celsius so we get 301.15 K. Change pressure from torr to atm, since 1 atm equals 760 torr. Thus, 743 torr turns into approximately 0.9776 atm. Utilizing the Ideal Gas Law, you can solve for moles (## Ideal Gas LawUse \( PV = nRT \) to solve for \( n \):\[ n = \frac{PV}{RT} \]Where:- \( P \) is pressure in atm,- \( V \) is volume in liters,- \( R \) is the constant (0.0821 L atm mol鈦宦� K鈦宦�), - \( T \) is temperature in Kelvin.In this calculation: \( n = \frac{(0.9776)(1.72)}{(0.0821)(301.15)} \approx 0.0732 \) moles.So, you have around 0.0732 moles of CO鈧� produced from these reactions.

Chemical equations detail the substances before and after a reaction. They must be balanced, meaning the amount of each element must be equal on both sides. This ensures mass is conserved.For the given chemical reactions:- **Magnesium Carbonate:** - The unbalanced equation is: \( MgCO_3 + HCl \rightarrow MgCl_2 + H_2O + CO_2 \) - Balanced becomes: \( MgCO_3 + 2HCl \rightarrow MgCl_2 + H_2O + CO_2 \)- **Calcium Carbonate:** - Unbalanced: \( CaCO_3 + HCl \rightarrow CaCl_2 + H_2O + CO_2 \) - Balanced turns to: \( CaCO_3 + 2HCl \rightarrow CaCl_2 + H_2O + CO_2 \)## Understanding BalancingEach reactant's atoms appear on both sides of the equations. We use coefficients, like '2' before HCl, to balance the number of atoms, confirming that neither matter nor energy is lost.

The Ideal Gas Law is a quintessential tool in chemistry, helping us relate different states of gas to its volume, amount, temperature, and pressure. It assumes gases behave ideally, meaning individual gas particles are point-like with no volume and no intermolecular forces. ## Formula Details- The law is shown as: \[ PV = nRT \] where: - \( P \) = pressure, - \( V \) = volume, - \( n \) = moles, - \( R \) = ideal gas constant (approximately 0.0821 L atm mol鈦宦� K鈦宦�), - \( T \) = temperature (in Kelvin).Plug in values for any three to find the fourth. For instance, given \( P \), \( V \), and \( T \), you can solve for \( n \), the number of moles, which tells you the quantity of gas available.## Application InsightConsider the scenario with CO鈧� gas: Knowing its pressure, volume, and temperature, you used the Ideal Gas Law to determine you had around 0.0732 moles of CO鈧�. This is crucial when you need to find out how much of a substance reacted to form another.

Mass percentage in a mixture indicates how much of one component exists compared to the total mass. It's a favorite in chemistry because it gives a clear, understandable comparison and accounts for all mixtures' parts.## Calculation in Steps1. **Determine Moles:** - Given total moles of CO鈧� from the reaction was 0.0732. 2. **Link Moles to Reactants:** - Both MgCO鈧� and CaCO鈧� produce CO鈧� in equal moles. - Let \( x \) be moles of MgCO鈧�; then \( (0.0732 - x) \) is for CaCO鈧�.3. **Mass Calculations:** - Mass of MgCO鈧�: \( x \times 84.31 \text{ g/mol} \) - Mass of CaCO鈧�: \( (0.0732 - x) \times 100.09 \text{ g/mol} \)4. **Mass Equation:** - Combine for total mass to solve: \[ 84.31x + 100.09(0.0732 - x) = 6.53 \text{ g} \]5. **MgCO鈧� Mass Finding:** - Solve the above equation to find \( x \approx 0.0597 \). - Mass of MgCO鈧� equals the moles times molar mass: \( 5.03 \text{ g} \)6. **Percentage Calculation:** - \( \frac{5.03}{6.53} \times 100 = 77.1\% \).This percentage reveals the dominance of magnesium carbonate in the mixture.