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The temperature of your water was 22.4 degrees Celsius. The volume of hydrogen collected was 37.1 mL. The atmospheric pressure in the lab room was 29.18 inches Hg. The difference in the water level between the beaker and the burette is 18.4 cm. What was the mass of the magnesium ribbon used?

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Final answer:

To calculate the mass of the magnesium ribbon used in the experiment, we need more information, such as the length or width of the ribbon or the density of the magnesium ribbon. Without this additional information, we cannot determine the mass of the ribbon.

Step-by-step explanation:

To calculate the mass of the magnesium ribbon used, we need to consider the reaction between magnesium and hydrochloric acid (assuming this is the experiment being conducted). The balanced chemical equation for this reaction is:

Mg + 2HCl → MgCl2 + H2

From the balanced equation, we know that the molar ratio between magnesium and hydrogen gas is 1:1. This means that for every 1 mole of magnesium reacted, 1 mole of hydrogen gas is produced.

To find the moles of hydrogen gas produced, we can use the Ideal Gas Law:

PV = nRT

Where:

P = pressure of the gas (in atm)

V = volume of the gas (in L)

n = number of moles of gas

R = ideal gas constant (0.0821 L·atm/mol·K)

T = temperature of the gas (in K)

We know the volume of hydrogen gas collected (37.1 mL) and the temperature (22.4 degrees Celsius, which is 295.55 K). However, we need to convert the pressure from inches Hg to atm.

1 atm = 29.92 inches Hg

First, let's convert the pressure to atm:

29.18 inches Hg * (1 atm / 29.92 inches Hg) = 0.973 atm

Next, let's convert the volume from mL to L:

37.1 mL * (1 L / 1000 mL) = 0.0371 L

Now, we can plug in the values into the Ideal Gas Law equation:

(0.973 atm) * (0.0371 L) = n * (0.0821 L·atm/mol·K) * (295.55 K)

Solving for n, we find:

n = (0.973 * 0.0371) / (0.0821 * 295.55)

n = 0.00127 moles

Since the molar ratio is 1:1 between magnesium and hydrogen gas, this means that 0.00127 moles of magnesium reacted.

Now we can calculate the molar mass of magnesium:

Molar mass of magnesium (Mg) = mass / moles

Molar mass of magnesium (Mg) = mass (grams) / 0.00127 moles

Given that the volume of the hydrogen gas collected was 37.1 mL and the difference in water level between the beaker and the burette is 18.4 cm, we need to find the mass of the magnesium ribbon. Unfortunately, the information provided does not provide enough information to directly find the mass of the magnesium ribbon. Additional information is needed, such as the length or width of the ribbon, or the density of the magnesium ribbon, in order to calculate its mass.

Therefore, without more information, we cannot determine the mass of the magnesium ribbon used.

User MaxwellLynn
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