20 POINTS!!
What is the enthalpy of combustion when 1 mol C6H6(g) completely reacts with oxygen?
2C6H6(g) + 15O2(g) ? 12CO2(g) + 6H2O(g)

Options:
A. - 6339 kJ/mol
B. - 3169 kJ/mol
C. 1268 kJ/mol
D. 6339 KJ/mol

Answer: The total energy, in kilojoules, that is needed to turn a 46 g block of ice at -25 degrees C into water vapor at 100 degrees C is 11.787 kJ.

Explanation:

Given: Mass = 46 g

Initial temperature = [tex]-25^{o}C[/tex]

Final temperature = [tex]100^{o}C[/tex]

Specific heat capacity of ice = 2.05 [tex]J/g^{o}C[/tex]

Formula used to calculate the energy is as follows.

[tex]q = m \times C \times (T_{2} - T_{1})[/tex]

where,

q = heat energy

m = mass

C = specific heat capacity

[tex]T_{1}[/tex] = initial temperature

[tex]T_{2}[/tex] = final temperature

Substitute the values into above formula as follows.

[tex]q = m \times C \times (T_{2} - T_{1})\\= 46 g \times 2.05 J/g^{o}C \times (100 - (-25))^{o}C\\= 11787.5 J (1 J = 0.001 kJ)\\= 11.787 kJ[/tex]

Thus, we can conclude that the total energy, in kilojoules, that is needed to turn a 46 g block of ice at -25 degrees C into water vapor at 100 degrees C is 11.787 kJ.

Answer:

B

Explanation:

The three functions of the stem:

Answer:

6g/cm³

Explanation:

Density of a substance can be calculated as follows:

Density = mass (g)/volume (cm³)

According to this question, a sample of silver has a volume of 6 cm³ and a mass of of 36g. The density will be

Density = 36/6

Density = 6g/cm³​

Answer:

They are sour. =)

Explanation:

Answer:

780 watts

Explanation:

formula to find power when given amps and voltage

P = A x V

=6.50a x 120V

= 780 W (watts)

Answer: The given compounds are identified as being made of ionic, covalent, or metallic bonds:

Explanation:

A bond formed by transfer of electrons from one atom to another is called an ionic bond. An ionic bond is formed between a metal atom and a non-metal atom.

A bond formed by transfer of electrons from one atom to another is called a covalent bond. A covalent bond is formed between two or more non-metal atoms only.

Steel is actually an alloy of carbon and iron where there is less than 2% carbon, 1% manganese and small amounts of silicon, phosphorus, oxygen and sulphur are present.

When atoms of metals are held together then bond formed between these atoms is called metallic bond.

Hence, steel is made of metallic bond.

Chemical formula of propane is [tex]CH_{3}CH_{2}CH_{3}[/tex] as there are only non-metal atoms are present. So, sharing of electrons takes place in such atoms due to which covalent bonding will be there.

Hence, propane is made up of covalent bonds.  

Calcium chloride contains a metal and a non-metal atom. This means that electrons are being transferred from calcium atom to the chlorine atom. Hence, bond present in calcium chloride is ionic bond.

Water has chemical formula [tex]H_{2}O[/tex]. Since, non-metal atoms are present there so sharing of electrons takes place between hydrogen and oxygen atoms. Hence, covalent bond is present in water.

Thus, we can conclude that given compounds are identified as being made of ionic, covalent, or metallic bonds:

Steel: ✔ metallic

Propane: ✔ covalent

Calcium chloride: ✔ ionic

Water: ✔ covalent

Answer: it consists of two simple machines: a lever and a wheel and axle. Effort is applied to the lever by picking up the handles of the wheelbarrow.

Explanation:

Answer:

B

Explanation:

B)

Answer:

fractional distillation since ot depends on the different liquids to have different boiling points

Answer:

Explanation:

a ) If N₂(g) and 3H₂(g) is added to the system , 2 moles of additional  ammonia will be produced .

b ) If pressure is decreased , less amount of ammonia will be formed, because forward reaction reduces the pressure. So, reaction will take place in reverse direction.

c ) Keq = [ NH₃ ] ² / [ N₂ ] [ H₂]³

d ) Substituting the given values in the equation ,

Keq = [ 6M ] ² / [ 3M] [ 4M]³

= 36 / 3 x 64 M⁻²

= 18.75 x 10⁻² M⁻² .

Answer:

Given nuclide is uranium-234.

If it undergoes beta decay then, what will be the daughter particle?

Explanation:

The beta particle decay increases the atomic number of the nuclide by one.

There is no change in the mass number of the nuclide.

The decay of beta particle from Uranium-234 is shown below:

It forms Np-93.

If the battery was removed, the energy produced by the battery would not be able to continue its path along the circuit.

Answer:

Explanation:

Hope this helps u!!

Answer:

0.0178

Explanation:

because you can work out the amount of moles in KOH using moles = mass/mr.

The mr of the KOH is 39.1+16+1=56.1 so you do

[tex] \frac{3}{56.1} [/tex]

which equals to 0.053475 so u 3SF which is 0.0535moles

than u uses the molar ratio which is 3 to 1

so 0.0535÷3=0.0178 which is the moles of FeCl3.

hope this make sense:)

Answer:

last option is correct.

Air molecules surrounding the metal will speed up and metal molecules will slow down

Explanation:

the metal cools when placed in room temperature air which causes surrounding air to heat up.

the speed of molecules slow down for any material which cools and molecules speed increases when any material heats up

Answer:

cvbn

Explanation:

Answer:

88,88 % de O y 11,11 % de H

Explanation:

La composición porcentual se define como la masa que hay de cada mol de átomo en 100g. Las moles de agua en 100g son:

Masa molar agua:

2H = 2*1g/mol = 2g/mol

1O = 1*16g/mol = 16g/mol

Masa molar = 2 + 16 = 18g/mol

100g H2O * (1mol / 18g) = 5.556 moles H2O.

Moles de hidrógeno:

5.556 moles H2O * (2mol H / 1mol H2O) = 11.11 moles H

Moles Oxígeno = Moles H2O = 5.556 moles

La masa de hidrógeno es:

11.11mol * (1g/mol) 11.11g H

La masa de oxígeno es:

5.556 mol * (16g / 1mol) = 88.89g O

Así, el porcentaje de O es 88.89% y el de H es 11.11%. La opción correcta es:

Answer: The student must add 2 infront of both [tex]H_2O[/tex] and [tex]SO_2[/tex] to make the equation balanced.

Explanation:

A balanced chemical equation is one where all the individual atoms are equal on both sides of the reaction. It follows the law of conservation of mass.

For the given unbalanced chemical equation:

[tex]2H_2S+3O_2\rightarrow H_2O+SO_2[/tex]

On the reactant side:

Atoms of H = 4

Atoms of S = 2

Atoms of O = 6

On the product side:

Atoms of H = 2

Atoms of S = 1

Atoms of O = 3

To balance the equation, a student must balance the atoms by adding 2 infront of both [tex]H_2O[/tex] and [tex]SO_2[/tex]

For the balanced chemical equation:

[tex]2H_2S+3O_2\rightarrow 2H_2O+2SO_2[/tex]

Option first 2.52 atm

Answer:

Solution given:

pressure 1[P1]=2.8atm

pressure 2[P2]=?

temperature [T1]=400k

temperature [T2]=360k

now

By using gas equation

P1V1/T1=P2V2/T2

since

volume is constant

P1/T1=P2/T2

2.8/400=P2/360

P2=2.8*360/400

P2= 2.52

Answer:

It's 2.52

Explanation:

This requires Gay-Lussac's Law, in which the relationship is P1 / T1 = P2 / T2. "P" stands for Pressure and "T" is Temperature. The first pressure is 2.80, the first temperature is 400 Kelvin, the second pressure is unknown (that's what your solving for), and your second temperature is 360 Kelvin. Because you don't have the second pressure, your equation will look like 2.80 atm x 360 K / 400. This will tell you that the pressure of the gas at 360 K will be 2.52.

I also took the test and it was correct.

Answer:

metal ores are naturally occurring rocks that contain metals or metal compounds in sufficient amounts to make it worthwhile extracting them

Answer:

See explanation

Explanation:

Natural gas is mined along with crude oil in many oil wells. It has the advantage of being a cheap fossil fuels which is easily obtainable.

Generally, natural gas is the cleanest of all the fossil fuels. This means that it is the fossil fuel that least contributes to environmental pollution.

On the other hand; natural gas produces some amount of sulphur as it is burnt and mercury as particulate matter. These substances are quite dangerous to health.

Secondly, the combustion of natural gas leads to the production of the oxides of nitrogen which play a key role in the occurrence of photochemical smog.

Answer:

pH = 6

Explanation:

Given that,

The concentration of [OH]⁻ ion is [tex]10^{-6}[/tex].

We need to find the pH of the solution.

We know that,

[tex]pH=-\log[OH]^-[/tex]

Put all the values,

[tex]pH=-\log(10^{-6})\\\\pH=6[/tex]

Hence, the pH of the solution is 6.

Explanation:

hope this helps u understand:)

Answer:

2.39×10¯⁵ m²

Explanation:

From the question given above, the following data were obtained:

Distance (d) = 8.08×10¯⁵ m

Charge (q) = 2.24×10¯⁹ C

Potential difference = 855 V

Area(A) =?

NOTE: Permittivity (ε₀) = 8.854×10¯¹² F/m

The area can be obtained as follow:

q = ε₀AV/d

2.24×10¯⁹ = 8.854×10¯¹² × A × 855 / 8.08×10¯⁵

2.24×10¯⁹ = 7.57×10¯⁹ × A / 8.08×10¯⁵

Cross multiply

7.75×10¯⁹ × A = 2.24×10¯⁹ × 8.08×10¯⁵

7.75×10¯⁹ × A = 1.81×10¯¹³

Divide both side by 7.75×10¯⁹

A = 1.81×10¯¹³ / 7.75×10¯⁹

A = 2.39×10¯⁵ m²

Thus, the area of the plate is 2.34×10¯⁵ m²

Answer:

2.39

Explanation:

Answer:

the answer is D (つ°ヮ°)つ （＾ω＾）

Answer:

6

Explanation:

6, because the number after decimals are considered significant but the 0 after the last number is not significant.

Ocean acidification is the process of decreased pH levels of the oceans. The burning of fossil fuels and industrialization are man-made activities that lead to this process.

Ocean acidification is an increased concentration of acidic components of the oceans due to an increase in the carbon dioxide level of the oceans.

Human activities like cutting down a large number of trees, discharging from industrial outlets, and burning fossils like petrol, coal, diesel, etc. are leading to increased acidification of the oceans.

Therefore, natural causes like increased salinity, flood, and earthquake are the reasons for oceanic acidification.

Learn more about ocean acidification here:

https://brainly.com/question/7604502

Answer:

Option D is good to go!

Explanation: as per the reactivity series more reactive substances will react with the counterpart substance.The most reactive substance here is calcium while the least reactive is aluminium, the magnesium comes in between.As per their reactivity, these substances will react with oxygen.

Explanation: