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3 years ago

A chemical engineer is studying the two reactions shown in the table below.

Chemistry

1 answer:

Kamila [148]3 years ago

4 0

Explanation:

Here are the answers. Do note that I had to convert the enthalpy to joules and temperature to Kelvin to make the unit for entropy work out.

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Why is carbon dioxide nonpolar?

vovikov84 [41]

CO2 is a linear molecule and the Oxygen (O) atoms on each end are symmetrical. Polarity results from an unequal sharing of valence electrons. Because of this symmetry there is no region of unequal sharing and CO2 is anonpolar molecule

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3 years ago

A student is asked to standardize a solution of potassium hydroxide. He weighs out 1.08 g potassium hydrogen phthalate (KHC8H4O4

natka813 [3]

Answer:

A. 0.143 M

B. 0.0523 M

Explanation:

Let's consider the neutralization reaction between potassium hydroxide and potassium hydrogen phthalate (KHP).

KOH + KHC₈H₄O₄ → H₂O + K₂C₈H₄O₄

The molar mass of KHP is 204.22 g/mol. The moles corresponding to 1.08 g are:

1.08 g × (1 mol/204.22 g) = 5.28 × 10⁻³ mol

The molar ratio of KOH to KHC₈H₄O₄ is 1:1. The reacting moles of KOH are 5.28 × 10⁻³ moles.

5.28 × 10⁻³ moles of KOH occupy a volume of 36.8 mL. The molarity of the KOH solution is:

M = 5.28 × 10⁻³ mol / 0.0368 L = 0.143 M

Let's consider the neutralization of potassium hydroxide and perchloric acid.

KOH + HClO₄ → KClO₄ + H₂O

When the molar ratio of acid (A) to base (B) is 1:1, we can use the following expression.

$M_{A} \times V_{A} = M_{B} \times V_{B}\\M_{A} = \frac{M_{B} \times V_{B}}{V_{A}} \\M_{A} = \frac{0.143 M \times 10.1mL}{27.6mL}\\M_{A} =0.0523 M$

8 0

3 years ago

Manganese dioxide (MnO2(s), Hf = –520.0 kJ) reacts with aluminum to form aluminum oxide (AI2O3(s), Hf = –1699.8 kJ/mol) and mang

Temka [501]

Answer : The enthalpy of the reaction = -1839.6 KJ

Solution : Given,

$\Delta (H_{f})_{MnO_{2}}$ = -520.0 KJ/mole

$\Delta (H_{f})_{Al_{2}O_{3}}$ = -1699.8 KJ/mole

The balanced chemical reaction is,

$3MnO_{2}(s)+4Al(s)\rightarrow 2Al_{2}O_{3}(s)+3Mn(s)$

Formula used :

$\Delta (H_{f})_{reaction}=\sum n(\Delta H_{f})_{product}-\sum n(\Delta H_{f})_{reactant}$

$\Delta (H_{f})_{reaction}=(2\times \Delta H_{Al_{2}O_{3}(s)}+3\times \Delta H_{Mn(s)} )-(3\times \Delta H_{MnO_{2}(s) }+4\times\Delta H_{Al}(s))$

We know that the standard enthalpy of formation of the element is equal to Zero.

Therefore, the enthalpy of formation of (Mn) and (Al) is equal to zero.

Now, put all the values in above formula, we get

$\Delta (H_{f})_{reaction}=[2moles\times (-1699.8 KJ/mole)}+3moles\times (0\text{ KJ/mole}})]-[(3moles\times(-520.0KJ/mole }+4moles\times(0\text{ KJ/mole})]$

= (-3399.6) + (1560)

= -1839.6 KJ

5 0

3 years ago

Why are hydrogen bonds so essential to the structure of dna?

Lelu [443]

Hydrogen bonds hold the paired nitrogenous bases together. Because hydrogen bonds are weak bonds, the two strands of DNA are easily separated a characteristic that is important to DNA's function.Hydrogen bonds form between adenine and thymine and between cytosine and guanine.

4 0

3 years ago

Type the correct answer in the box. Express your answer to two significant figures. An industrial vat contains 650 grams of soli

SashulF [63]

88.98 %

The Balance Chemical Equation is as follow,

2 HCl + Pb(NO₃)₂ → 2 HNO₃ + PbCl₂

According to equation,

331.2 g (1 mole) Pb(NO₃)₂ produces = 278.1 g (1 mole) PbCl₂

So,

870 g of Pb(NO₃)₂ will produce = X g of PbCl₂

Solving for X,

X = (870 g × 278.1 g) ÷ 331.2 g

X = 730.5 g of PbCl₂

Therefore,

Theoretical Yield = 730.5 g

Also as given,

Actual Yield = 650 g

So using following formula for percentage yield,

%age Yield = (Actual Yield / Theoretical Yield) × 100

Putting values,

%age Yield = (650 g / 730.5 g) × 100

%age Yield = 88.98 %

Brianliest please and thank you.

4 0

3 years ago