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How many moles of hydrogen are in 5.2 moles of C7H18

maksim [4K]

In one mole of C7H18 there are 18 moles of H (the number folowing the H)*
>> the ratio is 1:18

In 5.2 moles of C7H18 there are x moles of H
>> the ratio is 5.2:x

Cross multiply the two ratios
1x = 18×5.2
x = 93.6 moles of H

>> In 5.2 moles of C7H18 there are 93.6 moles of H

* This isnt a rule that you can always use.
However to find the mole of a certain element in a certain molucle all you have to do is count how many moles of the element are present in the molecule.
>> example1 >> H2O ;
2 H and 1 O

>> example2 >> CH3COOH ; [you add up all the moles of the same element]
(1+1) 2 C , (3+1) 4 H and (1+1) 2 O

>> example3 >> Mg(OH)2 ; [you multiply whetever is in parenthesis by the number after it 2] 1 Mg , (1×2) 2 O and (1×2) 2 H

6 0

4 years ago

Read 2 more answers

Calculate the initial rate for the formation of C at 25 ∘C, if [A]=0.50M and [B]=0.075M.

egoroff_w [7]

2.3*10^-2 M/s IS THE ANWSER<span>
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7 0

4 years ago

Which statement correctly relates two substances from this reaction?

Marta_Voda [28]

We have to know which two substances are related correctly.

The correct answer is: (C) H₃O⁺ is the conjugate acid of H₂O.

In an acid-base reaction, an acid reacts with a base and gives a conjugate base and conjugate acid. The reaction is shown below:

Acid₁ + Base₂ ⇄ Conjugate Base₁ + Conjugate Acid₂

In the reaction H₂CO₃ + H₂O ⇌ H₃O⁺ + HCO₃⁻, H₂CO₃ is an acid because it releases H⁺ ion and converts to HCO₃⁻. Here HCO₃⁻ is the conjugate base of H₂CO₃ ( according Arrhenius theory).

H₂O accepts H⁺ ion and is converted to H₃O⁺ , thus H₂O behaves as Bronsted base. So, H₃O⁺ is the conjugate acid of Bronsted base H₂O.

Hence, the correct answer is: (C) H₃O⁺ is the conjugate acid of H₂O.

5 0

4 years ago

if 14.0 g of aluminium reacts with excess sulfuric acid to produce 75.26 g of aluminium sulfate, what is the percent yield?

vlada-n [284]

Taking into account definition of percent yield, the percent yield for the reaction is 84.88%.

<h3>Reaction stoichiometry</h3>

In first place, the balanced reaction is:

2 Al + 3 H₂SO₄ → Al₂(SO₄)₃ + 3 H₂

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:

Al: 2 moles
H₂SO₄: 3 moles
Al₂(SO₄)₃. 1 mole
H₂: 3 moles

The molar mass of the compounds is:

Al: 27 g/mole
H₂SO₄: 98 g/mole
Al₂(SO₄)₃: 342 g/mole
H₂: 2 g/mole

Then, by reaction stoichiometry, the following mass quantities of each compound participate in the reaction:

Al: 2 moles ×27 g/mole= 54 grams
H₂SO₄: 3 moles ×98 g/mole= 294 grams
Al₂(SO₄)₃: 1 mole ×342 g/mole= 342 grams
H₂: 3 moles ×2 g/mole= 6 grams

<h3>Mass of aluminium sulfate formed</h3>

The following rule of three can be applied: if by reaction stoichiometry 54 grams of aluminium form 342 grams of aluminium sulfate, 14 grams of aluminium form how much mass of aluminium sulfate?

$mass of aluminium sulfate=\frac{14 grams of aluminium x342 grams of aluminium sulfate}{54 grams of aluminium}$

<u><em>mass of aluminium sulfate= 88.67 grams</em></u>

Then, 88.67 grams of aluminium sulfate can be produced if 14.0 g of aluminium reacts with excess sulfuric acid.

<h3>Percent yield</h3>

The percent yield is the ratio of the actual return to the theoretical return expressed as a percentage.

The percent yield is calculated as the experimental yield divided by the theoretical yield multiplied by 100%:

$percent yield=\frac{actual yield}{theorical yield} x100$

where the theoretical yield is the amount of product acquired through the complete conversion of all reagents in the final product, that is, it is the maximum amount of product that could be formed from the given amounts of reagents.

<h3>Percent yield for the reaction in this case</h3>

In this case, you know:

actual yield= 75.26 grams
theorical yield= 88.67 grams

Replacing in the definition of percent yields:

$percent yield=\frac{75.26 grams}{88.67 grams} x100$

Solving:

<u><em>percent yield= 84.88%</em></u>

Finally, the percent yield for the reaction is 84.88%.

Learn more about

the reaction stoichiometry:

brainly.com/question/24741074

brainly.com/question/24653699

percent yield:

brainly.com/question/14408642

#SPJ1

7 0

2 years ago

Which is the next logical step in balancing the given equation? CS2(1)+Cl2(g) CCl4(1) S2Cl2(1)

Mandarinka [93]

Reaction of current interest is:

<span>CS2(l) + Cl2(g) </span>→ <span>CCl4(l) + S2Cl2(l)

While balancing the chemical reaction, care must be taken that number of atoms of reactant side is equal to number of reactant on product side.

In present case, There is 1 'C' atom of both reactant and product side
There are 2 'S' atoms on both reactant and product side.
However, there are 2 Cl atoms of reactant side, but 6 Cl atoms on product side.
Hence multiplying Cl2 by 3, would equal the number of Cl atoms on both the sides.

Thus, the balanced reaction is
</span>CS2(l) + 3 Cl2(g) → CCl4(l) + S2Cl2(l)

7 0

3 years ago