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AleksandrR [38]

2 years ago

11

Molten gallium reacts with arsenic to form the semiconductor, gallium arsenide, GaAsGaAs, used in light emitting diodes and sola

r cells: Ga(l) + As(s) → GaAs(s)Ga(l) + As(s) → GaAs(s) If 4.00 gg of gallium is reacted with 5.50 gg of arsenic how many grams of the excess reactant are left at the end of the reaction?

1 answer:

jarptica [38.1K]2 years ago

6 0

Answer:

1.195 g of Arsenic.

Explanation:

Equation of the reaction:

Ga(l) + As(s) → GaAs(s).

Calculating the limiting reagent by:

Number of moles of:

Gallium:

Molar mass of Gallium = 69.7 g/mol.

Mass = 4 g

Number of moles = mass/molar mass

= 4/69.7

= 0.0574 mol.

Arsenic:

Molar mass of Arsenic = 75 g/mol.

Mass = 5.5 g

Number of moles = mass/molar mass

= 5.5/75

= 0.0733 mol

Therefore, using stoichiometry since 1 mole of Gallium reacted with 1 mole of Arsenic. The limiting reagent is Gallium.

Excess reagent is Arsenic.

Number of moles excess = 0.0733 - 0.0574

= 0.0159 moles

Mass of the excess Arsenic left =

Molar Mass * number of moles

= 0.0159 * 75

= 1.195 g of Arsenic.

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Answer:

$\boxed{\text{2700 J}}$

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Data:

m(HCl) = 50 g

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Calculations:

m = 50 + 50 = 100 g

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2 years ago

Which of the following statements is true about the following reaction?

MAVERICK [17]

The correct reaction equation is:

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Answer:

b) 1 mole of water is produced for every mole of carbon dioxide produced.

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a) <u>22.4 L of $CO_{2}$ gas</u> is produced only when <u> $\frac{22.4}{3}$ L of $C_{6}H_{8}O_{7}$ </u> is reacted with 22.4 L of $NaHCO_{3}$ . So it is wrong.

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c) $6.02\times 10^{23}$ molecules is equal 1 mole of $Na_{3}C_{6}H_{5}O_{7}$ if produced then 3 moles of $NaHCO_{3}$ is required, which is not given in the option. So it is wrong.

d) 54 g of water or 3 moles of $H_{2}O$ (<em>Molecular Weight of water is 18 g</em>) is produced when 3 moles of $NaHCO_{3}$ is used but in this option only one mole of $NaHCO_{3}$ is given. So it is wrong.

8 0

2 years ago

Read 2 more answers

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6 0

2 years ago

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2 years ago

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Effectus [21]

Answer:

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Explanation:

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Equatoing the atomic number of both sides

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Z = 38.

7 0

2 years ago