Compute 4.659×104−2.14×104. Round the answer appropriately.

What’s Silicon’s melting point?

torisob [31]

Answer:

2,577°F

Also,

Boron: 3,769°F (2,076°C)

Neon: -415.5°F (-248.6°C)

Beryllium: 2,349°F (1,287°C)

8 0

3 years ago

Read 2 more answers

P-fluoroanisole reacts with sulfur trioxide and sulfuric acid. Draw the major product of this substitution reaction; if applicab

Ipatiy [6.2K]

Answer: (Structure attached).

Explanation:

This type of reaction is an aromatic electrophilic substitution. The overall reaction is the replacement of a proton (H +) with an electrophile (E +) in the aromatic ring.

The aromatic ring in p-fluoroanisole has two sustituents, an halogen and a methoxy group, which are ortho-para directing substituents.

Aryl sulfonic acids are easily synthesized by an electrophilic substitution reaction aromatic using sulfur trioxide as an electrophile (very reactive).

The reaction occurs in three steps:

The attack on the electrophile forms the sigma complex.
The loss of a proton regenerates an aromatic ring.
The sulfonate group can be protonated in the presence of a strong acid (H₂SO₄).

Normally, a mixture of ortho-para substituted products would be obtained. However, since both para positions are occupied, only the ortho substituted product is obtained here.

8 0

3 years ago

Helppppppppppppppppppp me

masya89 [10]

The answer is A.
A pure substance is pure, so it cannot be separated in most cases.

8 0

4 years ago

Which statement defines specific heat capacity for a given sample

avanturin [10]

The statement that defines the specific heat capacity for a given sample is the quantity of heat that is required to raise 1 g of the sample by 1°C (Kelvin) at a constant pressure.

<h3>What is specific heat capacity?</h3>

Specific heat capacity is the of heat to increase the temperature per unit mass.

The formula to calculate the specific heat is Q = mct.

The options are attached here:

The temperature of a given sample is 1 %.
The temperature that a given sample can withstand.
The quantity of heat that is required to raise the sample's temperature by 1 °C1 °C (Kelvin).
The quantity of heat that is required to raise 1 g of the sample by 1°C (Kelvin) at a constant pressure.

Thus, the correct option is 4. The quantity of heat that is required to raise 1 g of the sample by 1°C (Kelvin) at a constant pressure.

Learn more about specific heat capacity

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8 0

2 years ago

The pH of a solution prepared by mixing 40.00 mL of 0.10 M NH3 with 50.00 mL of 0.10 M NH4Cl and 30mL of 0.05 M H2SO4 is 5.17. A

liq [111]

Answer:

Following are the answer to this question:

Explanation:

The value of pH solution is =5.17 So, the p^{OH}:

$p^{OH}$ =14-56.17

=8.823

The volume of the $NH_{3}$ = 40.00 ml

convert into the liter= 0.040L

The value of the concentrated $NH_{3}$ =0.10 M

The volume of the $NH_{4}Cl$ = 50.00 ml

convert into the liter= 0.050L

The value of concentrated $NH_{4}Cl$ = 0.10 M

The volume of the $H_{2}So_{4}$ = 30 ml

convert into the liter= 0.030L

The value of concentrated $H_2So_4$ =0.05 M

Calculating total volume=(0.40+0.050+0.030)

=0.120 L

calculating the new concentrated value of $NH_3$ = $\frac{0.10\times 0.040}{0.120}= 0.33 \ M$

calculating the new concentrated value of $NH_4Cl$ = $\frac{0.050\times 0.10}{0.120}= 0.04166 \ M$ calculating the new concentrated value of $H_2So_4= \frac{0.030\times 0.05}{0.120}= 0.0125 \ M$ when 1 mol $H_2So_4$ produced 2 mols $H^{+}$ so, 0.0125 in $H_2So_4$ produced:

$=4 \times (2 \times 0.0125) \ mol H^{+}\\\\= 0.025 mol H^{+}$

create the ICE table:

$NH_3 \ \ \ \ \ \ \ \ + H^{+} \ \ \ \ \ \ \longrightarrow NH_4^{+}$

I (m) 0.033(m) 0.025 0.04166

C -0.025 -0.025 + 0.025

E 8.3\times 10^{-3} 0 0.0667

now calculating pH:

when ph= 8.83:

$P^{H}= p^{kb}|+ \log\frac{[NH_4^{+}]}{[NH_3]}\\\\8.83=p^{kb}+\log\frac{0.0667}{8.3 \times 10^{-3}}\\\\p^{kb}=8.83-0.9069\\\\ \ \ \ =7.7231 \\\\\ The P^{kb} \ for \ NH_3 \ is =7.7231\\\\\ The P^{kb} \ for N^{+}H_4=14-7.7231\\\\\ \ \ \ \ \ =6.2769$

5 0

3 years ago