If 380. mL of 0.4294 M aqueous CaBr2 and 250. mL of 0.5880 M aqueous SO42- are reacted stoichiometrically according to the equation, how many mol of CaBr2 remained?

Al2(SO4)3(aq) + 3 CaBr2(aq) → 2 AlBr3(aq) + 3 CaSO4(s)
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If 270. mL of 0.08089 M aqueous Pb(NO3)2 and 710. mL of 0.05493 M aqueous Na+ are reacted stoichiometrically according to the equation, what mass (g) of Na+ remained?

Pb(NO3)2(aq) + 2 NaI(aq) → PbI2(s) + 2 NaNO3(aq)
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If 0.0490 mol of solid CaCO3 and 380 mL of 0.135 M aqueous H2SO4 are reacted, what volume (L) of gaseous CO2 measured at 1.1 atm pressure and 301 K is produced.

H2SO4(aq) + CaCO3(s) → CO2(g) + CaSO4(s) + H2O(l)

To find the number of moles of CaBr2 that remained, we need to determine the limiting reactant (the reactant that is completely consumed) and then use the stoichiometry of the balanced equation to calculate the number of moles.

Step 1: Calculate the number of moles of CaBr2 and SO42- using the given volumes and concentrations.

Number of moles of CaBr2 = volume (L) × concentration (mol/L)
= 0.380 L × 0.4294 mol/L
= 0.163532 mol

Number of moles of SO42- = volume (L) × concentration (mol/L)
= 0.250 L × 0.5880 mol/L
= 0.147 mol

Step 2: Use the stoichiometry of the balanced equation to determine the mole ratio between CaBr2 and SO42-.

From the balanced equation: Al2(SO4)3(aq) + 3 CaBr2(aq) → 2 AlBr3(aq) + 3 CaSO4(s)

The mole ratio between CaBr2 and SO42- is 3:1.

Step 3: Determine the limiting reactant.

To find the limiting reactant, compare the mole ratios between CaBr2 and SO42-. Since the ratio is 3:1, we need 3 moles of CaBr2 for every 1 mole of SO42-.

Using the mole ratios, we can see that we have excess SO42- (0.147 mol) compared to the available CaBr2 (0.163532 mol). Hence, CaBr2 is the limiting reactant.

Step 4: Calculate the number of moles of CaBr2 that remained.

Since CaBr2 is the limiting reactant, it is completely consumed in the reaction. Therefore, the number of moles of CaBr2 that remained is zero.

To solve the first question, we can use the stoichiometry of the balanced chemical equation to determine the amount of CaBr2 that reacts with the given amount of SO42-.

1. Calculate the number of moles of CaBr2:
Given volume = 380 mL = 0.380 L
Given concentration = 0.4294 M
Number of moles of CaBr2 = volume x concentration
= 0.380 L x 0.4294 mol/L

2. Use the stoichiometry of the balanced equation to find the ratio of moles of SO42- to moles of CaBr2:
From the balanced equation, the ratio is 3:1. This means that 3 moles of CaBr2 react with 1 mole of SO42-.

3. Calculate the number of moles of SO42-:
Given volume = 250 mL = 0.250 L
Given concentration = 0.5880 M
Number of moles of SO42- = volume x concentration
= 0.250 L x 0.5880 mol/L

4. Determine the limiting reagent:
Compare the number of moles of CaBr2 and SO42-. The reactant that has fewer moles is the limiting reagent.

5. Calculate the number of moles of CaBr2 that reacted:
Multiply the number of moles of the limiting reagent by the stoichiometric ratio of CaBr2 to SO42- (1:3).

6. Calculate the number of moles of CaBr2 that remained:
Subtract the number of moles of CaBr2 that reacted from the initial number of moles of CaBr2.

To solve the second question, follow the same steps using the given volumes and concentrations of Pb(NO3)2 and Na+ to calculate the number of moles for each and determine the limiting reagent. Then use the stoichiometry of the balanced equation to find the number of moles of Na+ that reacted and subtract it from the initial number of moles of Na+ to find the amount that remained.

To solve the third question, follow the same steps using the given number of moles of CaCO3 and volume and concentration of H2SO4 to calculate the number of moles for each and determine the limiting reagent. Use the stoichiometry of the balanced equation to find the number of moles of CO2 produced. Then, use the ideal gas law (PV = nRT) to calculate the volume of CO2 at the given pressure and temperature.