Which statement best describes how matter and energy is cycled through the ecosystem?

Find the effective resistance of the circuit

frozen [14]

300 ohms as you can add the individual resistances together

3 0

3 years ago

Air-bags can be inflated by the decomposition of sodium azide, NaN3. At 25.0◦C and 1.10 atm, what volume of N2(g) is produced by

Mashcka [7]

Answer:

V = 36.7L of $N_{2}$

Explanation:

1. Write the chemical reaction for the decomposition of sodium azide:

$_{2}NaN_{3}(l)=_{2}Na(s)+_{3}N_{2}(g)$

2. Find the number of moles of $N_{2}$ produced by the decomposition of 71.4g of $NaN_{3}$ :

$71.4gNaN_{3}*\frac{1molNaN_{3}}{65gNaN_{3}}*\frac{3molesN_{2}}{2molesNaN_{3}}=1.65molesN_{2}$

3. Use the ideal gas equation to find the Volume of $N_{2}$ occupied by 1.65 moles of $N_{2}$ , at the temperature and pressure given by the problem:

$PV=nRT$

Solving for V:

$V=\frac{nRT}{P}$

Converting the temperature from ◦C to K:

25◦C+273.15=298.15K

Replacing values:

$V=\frac{1.65mol*(0.082\frac{atm.L}{mol.K})*298.15K}{1.10atm}$

V=36.7L of $N_{2}$

4 0

3 years ago

Aluminum chloride can be formed from its elements:

saul85 [17]

Answer: The $\Deltas H^o_{formation}$ for the reaction is -1406.8 kJ.

Explanation:

Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.

According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.

The chemical reaction for the formation reaction of $AlCl_3$ is:

$2Al(s)+3Cl_2(g)\rightarrow 2AlCl_3 (s)$ $\Delta H^o_{formation}=?$

The intermediate balanced chemical reaction are:

(1) $HCl(g)\rightarrow HCl(aq.)$ $\Delta H_1=-74.8kJ$ ( × 6)

(2) $H_2(g)+Cl_2(g)\rightarrow 2HCl(g)$ $\Delta H_2=-185kJ$ ( × 3)

(3) $AlCl_3(aq.)\rightarrow AlCl_3(s)$ $\Delta H_3=+323kJ$ ( × 2)

(4) $2Al(s)+6HCl(aq.)\rightarrow 2AlCl_3(aq.)+3H_2(g)$ $\Delta H_4=-1049kJ$

The expression for enthalpy of formation of $AlCl_3$ is,

$\Delta H^o_{formation}=[6\times \Delta H_1]+[3\times \Delta H_2]+[2\times \Delta H_3]+[1\times \Delta H_4]$

Putting values in above equation, we get:

$\Delta H^o_{formation}=[(-74.8\times 6)+(-185\times 3)+(323\times 2)+(-1049\times 1)]=-1406.8kJ$

Hence, the $\Deltas H^o_{formation}$ for the reaction is -1406.8 kJ.

6 0

2 years ago

How many Sodium atoms are in 2.00 mols of Na2O

Anna71 [15]

There’s 1024 atoms of sodium in 2 moles of sodium

7 0

3 years ago

Which statement best describes a solution?

lara31 [8.8K]

A mixture having a uniform composition where the components can't be seen separately and all components are in the same state best describes a solution.

In chemistry, a solution is a homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent.

The correct answer between all the choices given is the third choice or letter C. I am hoping that this answer has satisfied your query and it will be able to help you in your endeavor, and if you would like, feel free to ask another question.

6 0

3 years ago

Read 2 more answers