Pls pls help me me pls

How many moles of Au2S3 is required to form 56 grams of H2S at STP?

Answer:

0.55 mol Au₂S₃

Explanation:

Normally, we would need a balanced equation with masses, moles, and molar masses, but we can get by with a partial equation, if the S atoms are balanced.

1. Gather all the information in one place:

M_r: 34.08

Au₂S₃ + … ⟶ 3H₂S + …

m/g: 56

2. Calculate the moles of H₂S

Moles of H₂S = 56 g H₂S × (34.08 g H₂S/1 mol H₂S)

= 1.64 mol H₂S

3. Calculate the moles of Au₂S₃

The molar ratio is 1 mol Au₂S₃/3 mol H₂S.

Moles of Au₂S₃ = 1.64 mol H₂S × (1 mol Au₂S₃/3 mol H₂S)

= 0.55 mol Au₂S₃

7 0

4 years ago

Based on the periodic table why are be, bg, ca and sr in the same column/group/family?

Lesechka [4]

Answer:

The elements are in the same column/group IIA.

See the explanation below, please.

Explanation:

The elements Calcium, Strontium, Beryllium, Magnesium, Barium and Radio, belong to the group of alkaline earth metals located in group IIA of the periodic table, they require 2 electrons to complete their octet (they have 2 valence electrons). reagents than alkali metals.

7 0

3 years ago

5

Archy [21]

Answer:

<h3>The answer is option C</h3>

Explanation:

The mass of a substance when given the density and volume can be found by using the formula

<h3>mass = Density × volume</h3>

From the question

volume of liquid = 15 mL

density = 2.5 g/mL

We have

mass = 15 × 2.5

We have the final answer as

Hope this helps you

6 0

3 years ago

How can constraints be used to help define the problem?

vitfil [10]

Answer:

Constraints are restrictions that need to be placed upon variables

Explanation:

Constraints are restrictions (limitations, boundaries) that need to be placed upon variables used in equations that model real-world situations. It is possible that certain solutions which make an equation true mathematically, may not make any sense in the context of a real-world word problem.

6 0

3 years ago

Using the following equation, 2C2H6 +7O2 -->4CO2 +6H2O, if 2.5g C2H6 react with 170g of O2, how many grams of water will be p

kirill [66]

The mass of water (H₂O) that would be produced is 4.5 g

<h3>Stoichiometry </h3>

From the question, we are to determine the mass of water that would be produced.

From the given balanced chemical equation

2C₂H₆ +7O₂ → 4CO₂ +6H₂O

This means

2 moles of C₂H₆ reacts with 7 moles of O₂ to produce 4 moles of CO₂ and 6 moles of H₂O

Now, we will determine the number of moles of each reactant present

For Ethane (C₂H₆)

Mass = 2.5 g

Molar mass = 30.07 g

Using the formula,

$Number\ of\ moles = \frac{Mass}{Molar\ mass}$

Number of moles of C₂H₆ present = $\frac{2.5}{30.07}$

Number of moles of C₂H₆ present = 0.08314 mole

For Oxygen (O₂)

Mass = 170g

Molar mass = 31.999 g/mol

Number of moles of O₂ present = $\frac{170}{31.999}$

Number of moles of O₂ present = 5.3127 moles

Since

2 moles of C₂H₆ reacts with 7 moles of O₂

Then,

0.08314 mole of C₂H₆ will react with $\frac{7 \times 0.08314 }{2}$

$\frac{7 \times 0.08314 }{2}$ = 0.58198 mole

Therefore,

0.08314 mole of C₂H₆ reacts with 0.58198 mole of O₂ to produce 3 × 0.08314 moles of H₂O

3 × 0.08314 = 0.24942 mole

Thus, the number of moles of water (H₂O) produced is 0.24942 mole

Now, for the mass of water that would be produced,

Using the formula,

Mass = Number of moles × Molar mass

Molar mass of water = 18.015 g/mol

Then,

Mass of water that would be produced = 0.24942 × 18.015

Mass of water that would be produced = 4.4933 g

Mass of water that would be produced ≅ 4.5 g

Hence, the mass of water (H₂O) that would be produced is 4.5 g

Learn more on Stoichiometry here: brainly.com/question/14271082

3 0

2 years ago