All categories

3 years ago

The reaction 4al (s) 3o2 (

2 answers:

8 0

The reaction 4al (s) 3o2 (
g. → 2al2o3 (s) δh° = -3351 kj is exothermic________, and therefore heat is _____release ___ by the reaction.

Hunter-Best [27]3 years ago

6 0

Answer: The reaction is exothermic and therefore the heat is released by the reaction.

Explanation:

There are 2 types of reaction based on the heat of the reaction:

Exothermic reactions are defined as the reactions in which energy is released in the form of heat. The enthalpy change $(\Delta H^o)$ of the reaction comes out to be negative for this kind of reaction.
Endothermic reactions are defined as the reactions in which energy is absorbed in the form of heat. The enthalpy change $(\Delta H^o)$ of the reaction comes out to be positive for this kind of reaction.

For the given chemical reaction:

$4Al(s)+3O_2(g)\rightarrow 2Al_2O_3(s);\Delta H^o=-3351kJ$

As, the enthalpy change of the reaction is negative. The reaction is considered as an exothermic reaction.

Hence, the reaction is exothermic and therefore the heat is released by the reaction.

You might be interested in

Which of the fallowing elements has the largest atomic radius?

expeople1 [14]

your answer is c hope this helps

6 0

3 years ago

A 2.50-l volume of hydrogen measured at â196 Â°c is warmed to 100 Â°c. calculate the volume of the gas at the higher temperature

ivann1987 [24]

To solve this we assume that the hydrogen gas is an ideal gas. Then, we can use the ideal gas equation which is expressed as PV = nRT. At a constant pressure and number of moles of the gas the ratio T/V is equal to some constant. At another set of condition of temperature, the constant is still the same. Calculations are as follows:

T1 / V1 = T2 / V2

V2 = T2 x V1 / T1

V2 = (100 + 273.15) K x 2.50 L / (-196 + 273.15) K

V2 = 12.09 L

Therefore, the volume would increase to 12.09 L as the temperature is increased to 100 degrees Celsius.

5 0

3 years ago

A sample of nitrogen gas is at a temperature of 50 c and a pressure of 2 atm. If the volume of the sample remains constant and t

Lilit [14]

Answer:

The new temperature of the nitrogen gas is 516.8 K or 243.8 C.

Explanation:

Gay-Lussac's law indicates that, as long as the volume of the container containing the gas is constant, as the temperature increases, the gas molecules move faster. Then the number of collisions with the walls increases, that is, the pressure increases. That is, the pressure of the gas is directly proportional to its temperature.

Gay-Lussac's law can be expressed mathematically as follows:

$\frac{P}{T} =k$

Where P = pressure, T = temperature, K = Constant

You want to study two different states, an initial state and a final state. You have a gas that is at a pressure P1 and at a temperature T1 at the beginning of the experiment. By varying the temperature to a new value T2, then the pressure will change to P2, and the following will be fulfilled:

$\frac{P1}{T1} =\frac{P2}{T2}$

In this case:

P1= 2 atm
T1= 50 C= 323 K (being 0 C= 273 K)
P2= 3.2 atm
T2= ?

Replacing:

$\frac{2 atm}{323 K} =\frac{3.2 atm}{T2}$

Solving:

$T2*\frac{2 atm}{323 K} =3.2 atm$

$T2=3.2 atm*\frac{323 K}{2 atm}$

T2= 516.8 K= 243.8 C

The new temperature of the nitrogen gas is 516.8 K or 243.8 C.

5 0

3 years ago

1. A gas sample at a pressure of 5.00 atm has a volume of 3.00 L. If the gas pressure is changed to 760 mm Hg, what volume will

tatyana61 [14]

Answer:

V₂ = 15.00 atm

Explanation:

Given data:

Initial pressure = 5.00 atm

Initial volume = 3.00 L

Final pressure = 760 mmHg ( 760/760 = 1 atm)

Final volume = ?

Solution:

P₁V₁ = P₂V₂

V₂ = P₁V₁ / P₂

V₂ = 5.00 atm × 3.00 L / 1 atm

V₂ = 15.00 atm

8 0

3 years ago

List five ways you use chemistry at home or school ?

Nat2105 [25]

1. cooking
2. cleaning
3.you use chemistry in science class (a.k.a. science experiments)
4. at your job depending on were you work

5 0

3 years ago