Explain, i don't understand.

7. for the combustion of ethyl alcohol as described in the above equation, which of the following is true?

8. the total volume of hydrogen gas is needed to fill the hindenburg was 2.00 × 10^8 at 1.00 atm and 25.1°c. how much energy was evolved when it burned?

7. A) I, II ; 8. D) 2.34e9 kJ

Step-by-step explanation:

7. Combustion of ethanol

I. The negative sign for ΔH shows that the reaction is exothermic.

II. The enthalpy change would be different if gaseous water were produced.

That's because it takes energy to convert liquid water to gaseous water, and this energy is included in the value of ΔH.

III. The reaction is a redox reaction, because

IV. The products of the reaction occupy a smaller volume than the reactants, because 3 mol of gaseous reactant are forming 2 mol of gaseous product.

Therefore, only I and II are correct.

7. Hindenburg

Data:

  V = 2.00 × 10⁸ L

  p = 1.00 atm

  T = 25.1 °C

ΔH = -286 kJ·mol⁻¹

Calculations:

(a) Convert temperature to kelvins

T = (25.1 + 273.15) K = 298.25 K

(b) Moles of hydrogen

Use the Ideal Gas Law:

pV = nRT

n = (pV)/(RT)

n = (1.00 × 2.00 × 10⁸)/(0.082 06 × 298.25) = 8.172 × 10⁶ mol

(c) Heat evolved

q = nΔH = 8.172 × 10⁶ × (-286) = -2.34 × 10⁹ kJ

The hydrogen in the Hindenburg released 2.34e9 kJ .

Answer:

Step-by-step explanation:

It is clear by the equation 2(27+3×35.5)= 267 gm of AlCl3 reacts with 6× 80 = 480 gm of Br2 . So 29.2 gm reacts = 480× 29.2/267= 52.6 gm

Calcium (Ca)(On the periodic table, ionization energy increases as you go up and to the right of the periodic table)

glycoproteins

Explanation:

A positive reaction for Molisch's test is given by almost all carbohydrates (exceptions include tetroses & trioses). It can be noted that even some glycoproteins and nucleic acids give positive results for this test (since they tend to undergo hydrolysis when exposed to strong mineral acids and form monosaccharides).

Answer:

Taking into accoun the ideal gas law, The volume of a container that contains 24.0 grams of N2 gas at 328K and 0.884 atm is 26.07 L.

An ideal gas is a theoretical gas that is considered to be composed of point particles that move randomly and do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.

The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:  

P×V = n×R×T

where P is the gas pressure, V is the volume that occupies, T is its temperature, R is the ideal gas constant, and n is the number of moles of the gas. The universal constant of ideal gases R has the same value for all gaseous substances.

Explanation:

In this case, you know:

P= 0.884 atm

V= ?

n= 0.857 moles (where 28 g/mole is the molar mass of N₂, that is, the amount of mass that the substance contains in one mole.)

R=0.082

T= 328 K

Replacing in the ideal gas law:

0.884 atm×V= 0.857 moles× 0.082 ×328 K

Solving:

V= 26.07 L

The volume of a container that contains 24.0 grams of N2 gas at 328K and 0.884 atm is 26.07 L.